[filmscanners] RE: Pixels and Prints
Hi David, How can a scanner have superior spectral response to a Bayer camera? Unless all the sensors seen the same thing, they aren't seeing the same thing. In a Bayer pattern sensor, each sensing element is seeing different light, unless there is a filter over the sensing elements that provides that function. Here's where we disagree: I don't see the lower spatial resolution for color affecting the spectral resolution for color. The actual measurements are identical (other than being first generation in digital, second in scans). Why do you keep bringing up 1st/2nd hand? The Bayer pattern image is in fact 2nd hand as well. It is in fact a resampling because of the Bayer pattern reconciliation, so it, too, is a second generation image. If you had the raw data, it would do you no good. So, I don't buy into this 2nd generation/1st generation argument. Also, with the Bayer pattern sensor, if a detail has a predominance in a particular color, and that falls on the sensor that isn't of that color, it'll be missed. That isn't as significant as it may sound, but it is significant, and reduces the fidelity of the overall system. So for features large enough to see, the Bayer camera is providing full color measurement. And with a lot lower noise than scanners. Lower noise? What you are calling lower noise is dubious. Perceived lower noise does not mean higher fidelity. How do you know it's lower noise? Have you actually done a comparison of it to the original image scene to see what was noise and what was not? The Bayer pattern reconciliation introduces substantial noise, it has to by nature. Also, lack of detail make it appear as less noise. Again, cartoons appear to have very little noise, and they have no detail. Film also has a higher image density capturing ability, which current CCDs do not, and as such. image density capturing ability??? If you are talking about dynamic range or latitude, the tests I've seen show the dSLRs superior to slide film. Dynamic range (NOT latitude, those are two entirely different things). I was talking about negative film, and no, there is no digital sensor that has the overall ability of negative film. Also, there's the issue of noise. Scanned film is a lot noisier than direct digital capture. Not necessarily true. Some may be, but that's due to poor film/scanner/development, as well as the perception that digital has less noise, when, in most cases, it isn't really less noise, but reduced fidelity. It also depends on how you measure noise, and what you classify as noise. It's simply not a 1:1 comparison. Just the noise problem alone makes scanned film problematic for color reproduction: the bit depth after the noise is much less than digital. My experience contradicts this. BTW, the 35mm camera/lenses you use for your scanning would be ;-) Regards, Austin Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
From: Austin Franklin Lower noise? What you are calling lower noise is dubious. Perceived lower noise does not mean higher fidelity. How do you know it's lower noise? Have you actually done a comparison of it to the original image scene to see what was noise and what was not? The Bayer pattern reconciliation introduces substantial noise, it has to by nature. Also, lack of detail make it appear as less noise. Again, cartoons appear to have very little noise, and they have no detail. I may regret getting involved in this discussion, but it's hard to let this pass. In real life, you don't have to compare a digital image to the original scene to know what's noise and what isn't. Blue sky is about as noiseless a source as you can find, so any noise you see is in the capture process. Also, a Bayer pattern interpolator doesn't introduce noise, unless it's processing an image that already looks like noise, and it can't find anything coherent to do edge detection on. But in that case, who cares? -- Ciao, Paul D. DeRocco Paulmailto:[EMAIL PROTECTED] Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
David, I think you have pre-judged the issue and are mixing emotional rhetoric with supportable and reproducible/verifiable results. your arguement that on a 'pixel level' film scans aren't the same quality as 10D images is a prime example. a) its not clear what comparison metric you are using b) what even 'pixel level' comparison itself means As was pointed out, a 2 pixel camera has brilliant sharpness, and if it is a Bayer sub-pixel layout, it will have the 'average' color balance of the scene capture pretty accurately. But at best it will be an impressionistic rendition of the scene. You also say WRT what kind of comparisons being made Someone argued that scanners produce better quality pixels because they measure all RGB, and I'm pointing out that this is wrong because scanned pixels are, in fact, worse than digital camera pixels. o o o Bayer images have very close to the right ratio of luminance to color resolution for viewing by humans. If you print a Bayer image at a high enough dpi that you are satisfied with the detail, then the color resolution will be good enough as well, so the interpolated pixels cheap shot is just that, a cheap shot. But other than insisting its 'worse than digital' you really haven't explained how and why it is worse. The 'dye cloud' of film acts most similarly to the Foveon sensor - capturing R,G,B information at each crystal/sub-pixel location simultaneously. A Bayer pattern does not. Which means that inherently the Bayer pattern sensor is creating data in the absence of existing data. Irrespective of how good the estimation equation is, it is still just that, an approximation. And like any mathematical model, it is provably susceptible to uncorrectable artifacts. The limit of the data that can be resolved on high end film, is higher than all but the most exceptional digital imagers. The math just proves this. The question therefore becomes - does a high resolution scan of this introduce sufficient optical defects that the end result is a lower data density than what you can capture from a 10D or similar. I don't think you have made the case that it is. Perhaps for a 1DS, but then you are looking at a capture device that has a resolution capability that is very close to the finest grained film data theoretic and empirical limits (just under 4000ppi scan rate). But the claim that a 10D is better than film isn't supported by the math or by visual inspection. - Original Message - From: David J. Littleboy [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Wednesday, October 22, 2003 7:43 PM Subject: [filmscanners] Re: Pixels and Prints Austin Franklin [EMAIL PROTECTED] writes: I think you've misunderstood what I've said. Take a 900 x 900 pixel crop from your 5080 dpi scan and print it at 3x3 inches. Take a 900x900 crop from a 10D image and print it at 3x3 inches. Which looks better? That depends, It doesn't depend. I've never seen a scan that was, on the pixel level, even close in quality to what the 10D produces. and I am curious why you think that is of any value? I'm curious too. I'm not the one making comments to the effect my scanner produces 210 MP when your digital camera only produces 6MP. If a 300 x 300 crop from a 10D represents 16x more area, why not compare actual area for area? Because that's a different question. Someone argued that scanners produce better quality pixels because they measure all RGB, and I'm pointing out that this is wrong because scanned pixels are, in fact, worse than digital camera pixels. (On an area for area basis, it seems digital wins, though. Most people comparing the 1Ds to 35mm find the 1Ds superior, and I suspect that even a 5080 dpi scan of a 15mm by 22.5mm section of film would look a lot worse at A4 than a 10D image would.) You're making the arbitrary choice of sensor sizes/metrics here. The pixel area from one is not necessarily of equal value to the pixel area from another, and what the equality is, depends on how many pixels there are for the respective image. I could downsample my scanner to give me the exact same image area information as the 10D, and that information would contain complete color values, not interpolated pixels. Bayer images have very close to the right ratio of luminance to color resolution for viewing by humans. If you print a Bayer image at a high enough dpi that you are satisfied with the detail, then the color resolution will be good enough as well, so the interpolated pixels cheap shot is just that, a cheap shot. If you print a scanned image at a high enough dpi that you are satisfied with the detail, then the color resolution will be insane overkill, unless your audience is Foveon equipped robots. Nothing wrong with insane overkill, it gets the job done. But it doesn't make a difference in the visual properties of the print. If you consider the minimum dpi for acceptable print to be a measure of (the inverse of) an imaging technology's pixel quality
[filmscanners] Re: Pixels and Prints
Karl writes, But the claim that a 10D is better than film isn't supported by the math or by visual inspection That wasn't my claim: my claim was that 900x900 pixels of a 1Ds image look a lot better than 900x900 pixels of a 4000 dpi scanned image if you print them at the same size. Please don't put words in my mouth. Do you think that I'm wrong in that??? David J. Littleboy [EMAIL PROTECTED] Tokyo, Japan Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
Hi Paul, Lower noise? What you are calling lower noise is dubious. Perceived lower noise does not mean higher fidelity. How do you know it's lower noise? Have you actually done a comparison of it to the original image scene to see what was noise and what was not? The Bayer pattern reconciliation introduces substantial noise, it has to by nature. Also, lack of detail make it appear as less noise. Again, cartoons appear to have very little noise, and they have no detail. I may regret getting involved in this discussion, but it's hard to let this pass. In real life, you don't have to compare a digital image to the original scene to know what's noise and what isn't. Blue sky is about as noiseless a source as you can find, so any noise you see is in the capture process. Blue sky is hardly noiseless. That doesn't mean that there can't be other sources of noise, some more significant than others, of course, but to assume that there is simply no noise in a blue sky is, IMO, a bad assumption. Do you have any actual data to back up this claim? I've analyzed a lot of sky, and certainly wouldn't make a generalization like that. Also, a Bayer pattern interpolator doesn't introduce noise, unless it's processing an image that already looks like noise, and it can't find anything coherent to do edge detection on. Of course the Bayer pattern reconciliation introduces noise, it has to by it's very nature. Any time you are interpolating, you have a high chance of introducing noise. Noise is, in this case, is introduced in both the spatial domain and the color domain. No field in real life (even sky) is entirely even, where all the values are exactly the same (or precisely linear) across a significant space. There are many different interpolation methodologies, of course, some better than others (and I've designed quite a few), but any interpolation algorithm used for Bayer pattern reconciliation will introduce noise. Regards, Austin Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
my claim was that 900x900 pixels of a 1Ds image look a lot better than 900x900 pixels of a 4000 dpi scanned image if you print them at the same size. David, Your terms are amorphous. looks a lot better in what regard? What may look a lot better to you, or to anyone else, may not look a lot better to someone else...depending on their experience and criteria. BTW, previously, your claim was from a 35mm camera...but you haven't listed what 35mm camera/film you used to do this comparison... I'll take it, since you listed the cameras you have, that you used one of the MF cameras you have to do this comparison. If that's true, then you should realize that typically, MF lenses are designed for a larger image circle than 35mm lenses, and therefore, that same 900x900 part of the film can be quite different... I, personally, note a difference when I zoom in and examine raw scanned pixels, between my Zeiss lenses for my Contax cameras, vs my Rollei 2.8F and even my Hasselblad. So, are you using MF for your comparison, or do you have a 35mm that you are doing this with? So, IMO, to make a fair/meaningful comparison, you should take into consideration the size difference in the sensor vs the film, and also qualify your criteria for better. Regards, Austin Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
From: Austin Franklin Blue sky is hardly noiseless. That doesn't mean that there can't be other sources of noise, some more significant than others, of course, but to assume that there is simply no noise in a blue sky is, IMO, a bad assumption. Do you have any actual data to back up this claim? I've analyzed a lot of sky, and certainly wouldn't make a generalization like that. First of all, when you look at digital images of the sky, you see some noise; when you look at the sky, you don't. But the point is that the amount of noise you get in the digital image depends upon the hardware, so it obviously can't all be actual noise coming from the sky. My old DiMage 7 is _very_ noisy, even at ISO 100. My Nikon LS-2000, scanning Kodachrome 25, or for that matter E6 slide film, has a lot of noise, presumably from film grain, too. My Canon 10D has much less noise in the final result. Of course the Bayer pattern reconciliation introduces noise, it has to by it's very nature. Any time you are interpolating, you have a high chance of introducing noise. Noise is, in this case, is introduced in both the spatial domain and the color domain. No field in real life (even sky) is entirely even, where all the values are exactly the same (or precisely linear) across a significant space. There are many different interpolation methodologies, of course, some better than others (and I've designed quite a few), but any interpolation algorithm used for Bayer pattern reconciliation will introduce noise. Noise is random, meaning that if you repeat the process, you get different answers. If you repeat the Bayer interpolation on the same raw data, you get the same answers. That's not noise, it's distortion. What's more, for real-world images, with the sort of detail on which people would recognize a loss of resolution, e.g., sharp edges, modern Bayer algorithims _correctly_ interpolate, producing what looks right to the eye. -- Ciao, Paul D. DeRocco Paulmailto:[EMAIL PROTECTED] Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
Hi Paul, when you look at the sky, you don't. How do you know you don't? But the point is that the amount of noise you get in the digital image depends upon the hardware, so it obviously can't all be actual noise coming from the sky. My old DiMage 7 is _very_ noisy, even at ISO 100. My Nikon LS-2000, scanning Kodachrome 25, or for that matter E6 slide film, has a lot of noise, presumably from film grain, too. My Canon 10D has much less noise in the final result. But that doesn't mean that every combination of film/scanner has noticeable noise generated by these things in sky regions. Noise is random Noise does not have to be random. It can be random, or deterministic. It's still noise. Anything that decreases fidelity is considered noise. , meaning that if you repeat the process, you get different answers. If you repeat the Bayer interpolation on the same raw data, you get the same answers. That's not noise, it's distortion. Distortion is noise. I really don't care what you want to call it, and I'm surprised you're arguing semantics here...instead of arguing the points. What's more, for real-world images, with the sort of detail on which people would recognize a loss of resolution, e.g., sharp edges, modern Bayer algorithims _correctly_ interpolate, producing what looks right to the eye. No, they don't %100 correctly interpolate the information %100 of the time (unless you're talking about someone with very diminished vision). Edges aren't always sharp, and sharp is really an amorphous term as well. I'd love to see some actual data you base this claim on...having written quite a few Bayer pattern reconciliation algorithms, I know it's just simply not true...and we did experiment with full three color data to see how well the algorithms worked. Looking right to the eye has nothing to do with fidelity of the image. Regards, Austin Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
From: Austin Franklin How do you know you don't? I dunno. How do I know this isn't all a dream? But that doesn't mean that every combination of film/scanner has noticeable noise generated by these things in sky regions. I assume drum scanners do much better, but they're a heck of a lot more expensive than a Canon Digital Rebel. Noise does not have to be random. It can be random, or deterministic. It's still noise. Anything that decreases fidelity is considered noise. Distortion is noise. I really don't care what you want to call it, and I'm surprised you're arguing semantics here...instead of arguing the points. This is not a semantic issue. Noise is _fundamentally_ different from distortion. For some purposes, distortion can be analyzed as though it was noise, but only in the case of things like quantization, where the spectrum of the distorion is noise-like. But the point here is that if a Bayer pattern generated noise then it would be filling in the pixels in some unpredictable, and therefore ultimately useless, manner. But it doesn't. On the sort of image detail that matters, modern Bayer interpolation algorithms do the Right Thing, and do so consistently and effectively. So while it's theoretically possible that a Bayer camera will miss a red dot on a white wall, because light from the red dot happens to fall only on a red pixel, who cares? Qualitatively, Bayer sensors work extremely well, so it's closer to the truth to say that a six-million sensor Bayer chip produces a six megapixel image than to say that it really only produces a 1.5 megapixel image. -- Ciao, Paul D. DeRocco Paulmailto:[EMAIL PROTECTED] Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
This discussions seems to have turned into how many pixels can dance on the head of a pen or as Brian Eno put it long ago: the heuristics of the mystics. Might I suggest that those of us who want to continue the discussion do so privately? Ellis Vener Disclaimer: This e-mail is intended to impart a sense of humor. Given e-mail's inability to carry inflections, tone and facial expressions it may fail miserably in its intent. The sender acknowledges the limitations of the technology and assigns to the software in which this message was composed any ill feelings that may arise. Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
Hi Paul, But that doesn't mean that every combination of film/scanner has noticeable noise generated by these things in sky regions. I assume drum scanners do much better, but they're a heck of a lot more expensive than a Canon Digital Rebel. As do high end CCD scanneras as well, and scanner operation is critical as well. Anyone can make a mess of most anything. Noise does not have to be random. It can be random, or deterministic. It's still noise. Anything that decreases fidelity is considered noise. Distortion is noise. I really don't care what you want to call it, and I'm surprised you're arguing semantics here...instead of arguing the points. This is not a semantic issue. Noise is _fundamentally_ different from distortion. Being a professional EE, and having designed many systems that deal specifically with noise (signal testing, audio and video), I disagree. I know of no precise definition of noise that would exclude distortion from being noise. Noise can have many sources, as can distortion...and fundamentally, they are the same...both are a reduction in the fidelity of the signal. But the point here is that if a Bayer pattern generated noise then it would be filling in the pixels in some unpredictable, and therefore ultimately useless, manner. But it doesn't. No one said the Bayer pattern generated noise. It's the Bayer pattern reconciliation (as in the interpolation used to fill in the missing color information) that can induce noise. As I've said, noise does not have to be unpredictable. It's simply a reduction in the fidelity of the reproduction of the original image, period. Call it what you want, I really don't care. On the sort of image detail that matters, modern Bayer interpolation algorithms do the Right Thing, and do so consistently and effectively. You say that, but I KNOW it's simply not true, and you're using amorphous terms like do the right thing...that's VERY unscientific, and hardly quantifiable. You also say it providing no basis for your claim, but your claim. If you have some actual data, please, I'd love to see it. I have direct personal experience with this, and I'm not sure you do. If you do, I'd like to hear it. So while it's theoretically possible that a Bayer camera will miss a red dot on a white wall, because light from the red dot happens to fall only on a red pixel, who cares? That isn't what's being talked about. It's not that it'll mis a red dot in the middle of a white wall, but that a red wall is made up of many gradients, and is not an even field. It may interpolate a point 98,132,12 that is in reality 112,138,12. Qualitatively, Bayer sensors work extremely well, so it's closer to the truth to say that a six-million sensor Bayer chip produces a six megapixel image than to say that it really only produces a 1.5 megapixel image. I agree completely with that, and have never said any differently (nor has anyone else in this discussion that I am aware of). But, to claim the Bayer patter reconciliation is %100 spot on is simply wrong. It may be decent, and in fact, quite decent, but it's not perfect. It is still, unarguably, a reduction in fidelity. The significance of that reduction is debatable, but it's still a reduction. Regards, Austin Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
Hi David, How can a scanner have superior spectral response to a Bayer camera? Unless all the sensors seen the same thing, they aren't seeing the same thing. In a Bayer pattern sensor, each sensing element is seeing different light, unless there is a filter over the sensing elements that provides that function. Also, they aren't really the same. The scanner sensor is, obviously, spectrally responding to the film. Film also has a higher image density capturing ability, which current CCDs do not, and as such. You also can't use Zone system compensation with an original CCD, but you can with film, and therefore have a far larger BW image density range than you would with a CCD. Number of places isn't relevant. A minimum number of components doesn't insure the least amount of distortion. But the errors a system introduces tends to be the product of the errors of each element in the system. Agreed, but if 6 elements are in a system, and each only produces a .001% error, and in another system there is only one element which produces .1% error, then, as I said, the number really is irrelevant. The other issue is color resolution. Since 4000dpi and higher scanned images are so much softer than digital images, they have, if anything, lower color resolution per pixel. Why do you claim they are softer? What, specifically, is softer? Because transitions at sharp edges in the image take more pixels. That simply means that the image is more accurately reproduced. Anyway, this really has nothing to do with color resolution...and I must admit, I'm surprised, knowing that you know as much as you do, that you say this. Softer or not, that is a detail issue, not a color resolution issue. We seem to be agreeing hereg: spectral response and spatial response are different. That's good, I hadn't seen you clarify which you were talking about, and wanted to make sure we were both talking about the same thing. ...If 35mm film only had, as you said I believe, 2700PPI of image data, then all the people who have high end Imacon/Leaf/Drum scanners have simply wasted their money...yet all of us can clearly get better images out of scanning using these higher SPI scanners... Isn't most of that cleaning up the grain? AS I mentioned, that really depends on the film/exposure/development. In some cases, yes, of course...TMax 3200 would really make a mess ;-) The Minolta 5400 samples of actual images show no real advantage over even 2700 dpi scans, but grain aliasing is a lot less obnoxious. I would certainly believe that with certain films, and I also can't speak at all about the Minolta 5400 as I am unfamiliar with the design of that scanner, so I can't say if it's good or bad... What scanner/film/development/camera etc. do you use to base your statements on 35mm film on? Nikon 8000; Provia 100F, Velvia 100F, Reala; Fuji GS645S, Rolleiflex, Mamiya 645. Good scanner, good film...but I don't see any 35mm cameras there, and after all, we were talking about 35mm, weren't we? ;-) I also have a GS645 (not S) and love it, but it's way too sharp and really needs to be stopped down...not for sharpness, but for what it does to the out of focus areas... I also use a number of Rolleiflexs...2.8F both Xenotar and Planar (no, I haven't done any tests with the lenses yet ;-) and a 6008...all superb cameras. You should be able to get some simply stunning images from the Rolleis and your scanner. BTW, MF lenses are not going to give you as sharp an image per pixel as 35mm will, simply because of lense design considerations due to the area coverage. If you want to to see what 35mm is capable of, get some Contax and a Zeiss lense, most of which are very sharp, and have pleasing OOF area renderings... Regards, Austin Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
Austin Franklin [EMAIL PROTECTED] writes: How can a scanner have superior spectral response to a Bayer camera? Unless all the sensors seen the same thing, they aren't seeing the same thing. In a Bayer pattern sensor, each sensing element is seeing different light, unless there is a filter over the sensing elements that provides that function. Here's where we disagree: I don't see the lower spatial resolution for color affecting the spectral resolution for color. The actual measurements are identical (other than being first generation in digital, second in scans). Note that even with three measurements at each point, the colors at features smaller than the resolution of the system will be wrong. And there's always an antialiasing filter. And we're looking at it with low-chrominance (spatial) resolution eyes. If you print a Bayer captured image at a dpi density such that the luminance resolution is adequate, the chrominance resolution will be as well. So for features large enough to see, the Bayer camera is providing full color measurement. And with a lot lower noise than scanners. Also, they aren't really the same. The scanner sensor is, obviously, spectrally responding to the film. Which has already introduced infelicities in the spectral response. Film also has a higher image density capturing ability, which current CCDs do not, and as such. image density capturing ability??? If you are talking about dynamic range or latitude, the tests I've seen show the dSLRs superior to slide film. If you are talking about a per-unit-area-of -sensor comparison, dSLRs win in most comparisons I've seen. Just thinking about an 8x10 made from a 22x15mm area of film is enough to make one shudder. Also, there's the issue of noise. Scanned film is a lot noisier than direct digital capture. Just the noise problem alone makes scanned film problematic for color reproduction: the bit depth after the noise is much less than digital. You also can't use Zone system compensation with an original CCD, but you can with film, and therefore have a far larger BW image density range than you would with a CCD. DSLRs are certainly problematic for BW, but you can't use Zone system with color films (color shifts on push/pull), and you can't really use the zone system with 35mm BW (even N+1 processing makes the grain problematic and N+2 is really unreasonable). David J. Littleboy [EMAIL PROTECTED] Tokyo, Japan Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
I'm guessing here, based upon what seems logical to me. I'm sure Austin knows a lot more about this stuff than I. Here's my best guess: I assume the sensor element responds as a unique unit, at the moment it gathers the light information, so I also assume it responds in some manner by generating a voltage level based upon the total amount of photons falling on it's overall surface area. I believe CCDs also have an overflow device to drain off excessive light exposure, so it doesn't jump or discharge to other adjacent sensor elements. I don't know what type of curves the sensors have, in terms of if they are relatively linear or not, but it would seem to make sense (at least to me) to have the CCD respond to all the photons hitting the sensor surface area (until overload), which might be total sum of rather than an average, however, I would think that would have the same basic result. Art Bob Frost wrote: Art, Austin, et al., Does a sensor 'average' the light falling on it, or does it use some other mathematical function? Bob Frost. - Original Message - From: Arthur Entlich [EMAIL PROTECTED] However, within its resolution, it accurately represents the average hue and luminosity that the film represents in that pixel location. Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
Yes, you are correct. Art [EMAIL PROTECTED] wrote: This didn't start out as a film vs digital comparison but a scanned film vs digital one. So both images have hard pixels. Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
Thanks Darrell! The link does offer some good information on the subject and does help answer some of the questions - even the recent one involving the 240ppi vrs 720 ppi numbers. According to the information on the document, all incoming resolutions except the printers native resolution are resampled which means that if they had been resampled once already they will have undergone a resampling of the resample which can lead to poorer quality outputs. The document assumed that those files with the printers native resolution are not resampled but just passed thru for further processing by the printer driver; however, I am not so sure that this is the case without additional explanation or evidence that the printers are that discriminating. I am inclined to think that as a matter of general practice they perform an resampling process on all incoming files regardless of their resolutions, which means that a perfectly good 720 ppi incoming file will be altered in accordance with the next neighbor formula so as to remain at 720 ppi but with charafteristics different from what the original 720 ppi was. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Darrell Sent: Thursday, October 23, 2003 11:20 PM To: [EMAIL PROTECTED] Subject: [filmscanners] RE: Pixels and Prints Hi all Good question Laurie. I see you have asked it several times. The one about what the printer does with the binary data you send it. I vaguely recalled seeing this explained, so it didn't take long to find this link http://www.ddisoftware.com/qimage/quality/ The Lanczos interpolation really does seem to make a difference. Darrell --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.528 / Virus Database: 324 - Release Date: 10/16/2003 Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
I also suspect that the printer driver will always touch the binary data flow. It would have to for control of how and where the inks are laid down. There is also the issue of color gamut, though you do have some degree of control if you are using some color management solution that includes ICC profiles. I do know that third party printing software claims to use more complex algorithms and proprietary print drivers that bypass the printer manufacturers own drivers. By this method they directly control the printer and its printing patterns for superior quality. My trial use of QImage, in particular, seems to prove out this quality aspect on the Epson 2000 full size prints. There is another application that I am aware of called Piezography BW that uses a special printer driver and inks to acheive outstanding BW prints. Link to a review here http://www.computer-darkroom.com/piezo/piezo_1.htm There are claims that Epson data states the input resolution - the resolution at which data is rasterized - is 720 dpi for desktops and 360 dpi for wide formats. Less understandable is the Epson recommendation of 300 ppi at the size you intend to print as their new magic number; if you get to 220 or less, you start to see a difference in image quality, and conversely, you won't see much improvement with bitmapped images by going over 300 ppi. Hewlett-Packard, whose printheads are based on a 600-dpi resolution instead of 720, recommends 150-200 ppi at final size for its inkjet printers. The above paragraph contains information from Mastering Digital Printing, which includes everything you wanted to know about digital printing, EXCEPT whether or not a 720 ppi file sent to an Epson printer is modified in any way by the printer driver. Unless I missed the point, that is the question we are trying to answer here. In my experience, this third party software (QImage) takes MUCH LONGER to print. Using this as a clue, I would say that there is more detailed calculation going on before the file is sent to the printer, even at 720 ppi. I believe the conversion of pixels to dots must involve some interpolation by the printer driver, even at the native resolution. When using these different software, one would of course have to profile their printer using the particular print engine. Darrell -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of LAURIE SOLOMON Sent: Friday, October 24, 2003 9:48 AM To: [EMAIL PROTECTED] Subject: [filmscanners] RE: Pixels and Prints Thanks Darrell! The link does offer some good information on the subject and does help answer some of the questions - even the recent one involving the 240ppi vrs 720 ppi numbers. According to the information on the document, all incoming resolutions except the printers native resolution are resampled which means that if they had been resampled once already they will have undergone a resampling of the resample which can lead to poorer quality outputs. The document assumed that those files with the printers native resolution are not resampled but just passed thru for further processing by the printer driver; however, I am not so sure that this is the case without additional explanation or evidence that the printers are that discriminating. I am inclined to think that as a matter of general practice they perform an resampling process on all incoming files regardless of their resolutions, which means that a perfectly good 720 ppi incoming file will be altered in accordance with the next neighbor formula so as to remain at 720 ppi but with charafteristics different from what the original 720 ppi was. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Darrell Sent: Thursday, October 23, 2003 11:20 PM To: [EMAIL PROTECTED] Subject: [filmscanners] RE: Pixels and Prints Hi all Good question Laurie. I see you have asked it several times. The one about what the printer does with the binary data you send it. I vaguely recalled seeing this explained, so it didn't take long to find this link http://www.ddisoftware.com/qimage/quality/ The Lanczos interpolation really does seem to make a difference. Darrell --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.528 / Virus Database: 324 - Release Date: 10/16/2003 Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
Austin Franklin [EMAIL PROTECTED] writes: Because that's a different question. Someone argued that scanners produce better quality pixels because they measure all RGB, and I'm pointing out that this is wrong because scanned pixels are, in fact, worse than digital camera pixels. It's not wrong. If you are talking image fidelity, then it depends on what aspect of image fidelity is more important to you. CLEARLY the scanned pixel has higher color fidelity...and it may in fact have higher image detail fidelity as well... Even if the digicam image is sharper, sharpness may not mean higher image fidelity. You seem to have a conflation of concepts here. To my ear color fidelity should mean something on the order of the ability to accurately reproduce colors. Scanners, the film itself, and direct digital capture all use the same concept for color reproduction (three measurements to approximate an infinite distribution), and so there isn't a conceptual difference between RGB from a scanner and RGB from a digital camera. If anything, the scanner is going to be worse, because you have the scanner's spectral response interpreting the film's spectral response. Two places for things to go wrong as opposed to one. The other issue is color resolution. Since 4000dpi and higher scanned images are so much softer than digital images, they have, if anything, lower color resolution per pixel. Of course, color resolution is largely irrelevant. The human eye has abysmally poor color resolution, and Bayer sensors have an appropriate ratio of luminance to color resolution. So it seems to me that the sense of unhappiness with Bayer color that many people have is completely unjustified/misplaced. The only question is what pixel density do you need to print at to get the image quality you want. There are lots of people who come up with 9MP or so as the digital equivalent of 35. And there's a lot who come up with 16M, and 24M and 96M etc. People who see a 35mm frame as having 24MP of information are seriously dizzy. A file with a full 24 MP of dSLR quality pixels would be a thing of amazing beauty. Stitch together four 6MP dSLR images and print it at 16x24, and you'll have a print that 35mm can never dream of, whatever printing technology you use. David J. Littleboy [EMAIL PROTECTED] Tokyo, Japan Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
I also suspect that the printer driver will always touch the binary data flow. I am not sure that is in question. What may be in question is if the resampling of the incoming file to the native resolution is in effect that same sort of thing as the post interpetation processing of the data by the print driver which would include conversion from RGB to CYMK, the application of dithering, and adjustments to the color profile of the image data being processed. To be sure they can all have an impact; but I doubt if the latter's impact will generate the sorts of problems that the former might have. The imact of the latter would be of a different type and nature. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Darrell Sent: Friday, October 24, 2003 12:07 PM To: [EMAIL PROTECTED] Subject: [filmscanners] RE: Pixels and Prints I also suspect that the printer driver will always touch the binary data flow. It would have to for control of how and where the inks are laid down. There is also the issue of color gamut, though you do have some degree of control if you are using some color management solution that includes ICC profiles. I do know that third party printing software claims to use more complex algorithms and proprietary print drivers that bypass the printer manufacturers own drivers. By this method they directly control the printer and its printing patterns for superior quality. My trial use of QImage, in particular, seems to prove out this quality aspect on the Epson 2000 full size prints. There is another application that I am aware of called Piezography BW that uses a special printer driver and inks to acheive outstanding BW prints. Link to a review here http://www.computer-darkroom.com/piezo/piezo_1.htm There are claims that Epson data states the input resolution - the resolution at which data is rasterized - is 720 dpi for desktops and 360 dpi for wide formats. Less understandable is the Epson recommendation of 300 ppi at the size you intend to print as their new magic number; if you get to 220 or less, you start to see a difference in image quality, and conversely, you won't see much improvement with bitmapped images by going over 300 ppi. Hewlett-Packard, whose printheads are based on a 600-dpi resolution instead of 720, recommends 150-200 ppi at final size for its inkjet printers. The above paragraph contains information from Mastering Digital Printing, which includes everything you wanted to know about digital printing, EXCEPT whether or not a 720 ppi file sent to an Epson printer is modified in any way by the printer driver. Unless I missed the point, that is the question we are trying to answer here. In my experience, this third party software (QImage) takes MUCH LONGER to print. Using this as a clue, I would say that there is more detailed calculation going on before the file is sent to the printer, even at 720 ppi. I believe the conversion of pixels to dots must involve some interpolation by the printer driver, even at the native resolution. When using these different software, one would of course have to profile their printer using the particular print engine. Darrell -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of LAURIE SOLOMON Sent: Friday, October 24, 2003 9:48 AM To: [EMAIL PROTECTED] Subject: [filmscanners] RE: Pixels and Prints Thanks Darrell! The link does offer some good information on the subject and does help answer some of the questions - even the recent one involving the 240ppi vrs 720 ppi numbers. According to the information on the document, all incoming resolutions except the printers native resolution are resampled which means that if they had been resampled once already they will have undergone a resampling of the resample which can lead to poorer quality outputs. The document assumed that those files with the printers native resolution are not resampled but just passed thru for further processing by the printer driver; however, I am not so sure that this is the case without additional explanation or evidence that the printers are that discriminating. I am inclined to think that as a matter of general practice they perform an resampling process on all incoming files regardless of their resolutions, which means that a perfectly good 720 ppi incoming file will be altered in accordance with the next neighbor formula so as to remain at 720 ppi but with charafteristics different from what the original 720 ppi was. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Darrell Sent: Thursday, October 23, 2003 11:20 PM To: [EMAIL PROTECTED] Subject: [filmscanners] RE: Pixels and Prints Hi all Good question Laurie. I see you have asked it several times. The one about what the printer does with the binary data you send it. I vaguely recalled seeing this explained, so it didn't take long to find this link http://www.ddisoftware.com/qimage/quality
[filmscanners] RE: Pixels and Prints
I just re-read what I wrote and see that it needs to be corrected to make it clearer and easier to read and understand. What may be in question is if the resampling of the incoming file to the native resolution is in effect that same sort of thing as the post interpetation processing of the data by the print driver which would include conversion from RGB to CYMK, the application of dithering, and adjustments to the color profile of the image data being processed. This should read: What may be in question is if the resampling of the incoming file to the native resolution is in effect the same sort of thing as the post interpolation processing of the data by the print driver which would include conversion from RGB to CYMK, the application of dithering, and adjustments to the color profile of the image data being processed. To be sure they can all have an impact; but I doubt if the latter's impact will generate the sorts of problems that the former might have. This should read: To be sure they can all have an impact; but I doubt if the latter's impact will generate the same sorts of problems that the former might produce. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of LAURIE SOLOMON Sent: Friday, October 24, 2003 9:40 PM To: [EMAIL PROTECTED] Subject: [filmscanners] RE: Pixels and Prints I also suspect that the printer driver will always touch the binary data flow. I am not sure that is in question. What may be in question is if the resampling of the incoming file to the native resolution is in effect that same sort of thing as the post interpetation processing of the data by the print driver which would include conversion from RGB to CYMK, the application of dithering, and adjustments to the color profile of the image data being processed. To be sure they can all have an impact; but I doubt if the latter's impact will generate the sorts of problems that the former might have. The imact of the latter would be of a different type and nature. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Darrell Sent: Friday, October 24, 2003 12:07 PM To: [EMAIL PROTECTED] Subject: [filmscanners] RE: Pixels and Prints I also suspect that the printer driver will always touch the binary data flow. It would have to for control of how and where the inks are laid down. There is also the issue of color gamut, though you do have some degree of control if you are using some color management solution that includes ICC profiles. I do know that third party printing software claims to use more complex algorithms and proprietary print drivers that bypass the printer manufacturers own drivers. By this method they directly control the printer and its printing patterns for superior quality. My trial use of QImage, in particular, seems to prove out this quality aspect on the Epson 2000 full size prints. There is another application that I am aware of called Piezography BW that uses a special printer driver and inks to acheive outstanding BW prints. Link to a review here http://www.computer-darkroom.com/piezo/piezo_1.htm There are claims that Epson data states the input resolution - the resolution at which data is rasterized - is 720 dpi for desktops and 360 dpi for wide formats. Less understandable is the Epson recommendation of 300 ppi at the size you intend to print as their new magic number; if you get to 220 or less, you start to see a difference in image quality, and conversely, you won't see much improvement with bitmapped images by going over 300 ppi. Hewlett-Packard, whose printheads are based on a 600-dpi resolution instead of 720, recommends 150-200 ppi at final size for its inkjet printers. The above paragraph contains information from Mastering Digital Printing, which includes everything you wanted to know about digital printing, EXCEPT whether or not a 720 ppi file sent to an Epson printer is modified in any way by the printer driver. Unless I missed the point, that is the question we are trying to answer here. In my experience, this third party software (QImage) takes MUCH LONGER to print. Using this as a clue, I would say that there is more detailed calculation going on before the file is sent to the printer, even at 720 ppi. I believe the conversion of pixels to dots must involve some interpolation by the printer driver, even at the native resolution. When using these different software, one would of course have to profile their printer using the particular print engine. Darrell -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of LAURIE SOLOMON Sent: Friday, October 24, 2003 9:48 AM To: [EMAIL PROTECTED] Subject: [filmscanners] RE: Pixels and Prints Thanks Darrell! The link does offer some good information on the subject and does help answer some of the questions - even the recent one involving the 240ppi vrs 720 ppi numbers. According to the information on the document, all incoming
[filmscanners] RE: Pixels and Prints
Hi David, Austin Franklin [EMAIL PROTECTED] writes: Because that's a different question. Someone argued that scanners produce better quality pixels because they measure all RGB, and I'm pointing out that this is wrong because scanned pixels are, in fact, worse than digital camera pixels. It's not wrong. If you are talking image fidelity, then it depends on what aspect of image fidelity is more important to you. CLEARLY the scanned pixel has higher color fidelity...and it may in fact have higher image detail fidelity as well... Even if the digicam image is sharper, sharpness may not mean higher image fidelity. You seem to have a conflation of concepts here. To my ear color fidelity should mean something on the order of the ability to accurately reproduce colors. That is what fidelity means... Scanners, the film itself, and direct digital capture all use the same concept for color reproduction (three measurements to approximate an infinite distribution), and so there isn't a conceptual difference between RGB from a scanner and RGB from a digital camera. No, but you seem to be missing that they can each have different abilities to reproduce color accurately. A microphone from a telephone and a high end studio microphone both use the same concept, but their ability to accurately reproduce audio is entirely different. If anything, the scanner is going to be worse, because you have the scanner's spectral response interpreting the film's spectral response. Two places for things to go wrong as opposed to one. Number of places isn't relevant. A minimum number of components doesn't insure the least amount of distortion. The other issue is color resolution. Since 4000dpi and higher scanned images are so much softer than digital images, they have, if anything, lower color resolution per pixel. Why do you claim they are softer? What, specifically, is softer? Anyway, this really has nothing to do with color resolution...and I must admit, I'm surprised, knowing that you know as much as you do, that you say this. Softer or not, that is a detail issue, not a color resolution issue. Of course, color resolution is largely irrelevant. The human eye has abysmally poor color resolution, and Bayer sensors have an appropriate ratio of luminance to color resolution. Now hold on. Are you talking spatial resolution of color, or ability to discern tones? If you are talking the former, yes, our ability to discern colors spatially is lower than our ability to discern detail, but as far as discerning tonality, that is just not true. We can discern more color tones than gray tones, by a huge margin...and our ability to discern color tones is in fact superb. Something on the order of 16M tones the human eye can discern. That's pretty high resolution. So it seems to me that the sense of unhappiness with Bayer color that many people have is completely unjustified/misplaced. The only question is what pixel density do you need to print at to get the image quality you want. There are lots of people who come up with 9MP or so as the digital equivalent of 35. And there's a lot who come up with 16M, and 24M and 96M etc. People who see a 35mm frame as having 24MP of information are seriously dizzy. I'm not sure what you base that on really, as it's simply wrong. If 35mm film only had, as you said I believe, 2700PPI of image data, then all the people who have high end Imacon/Leaf/Drum scanners have simply wasted their money...yet all of us can clearly get better images out of scanning using these higher SPI scanners... A file with a full 24 MP of dSLR quality pixels would be a thing of amazing beauty. Stitch together four 6MP dSLR images and print it at 16x24, and you'll have a print that 35mm can never dream of, whatever printing technology you use. Seriously, I really think you need to update your film/processing/exposure/scanning if you believe what you believe and what you believe is based on your real experience you have. Or, perhaps, you simply like processed images, that lack high detail, but are sharp...and that's fine, but that doesn't make one better than the other, it's simply your personal preference. What scanner/film/development/camera etc. do you use to base your statements on 35mm film on? Regards, Austin Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
David J. Littleboy wrote: The question is what the cutoff point is. It looks to me that 35mm film is worth about 9MP, not 24MP. Most people comparing the 1Ds to 35mm film find the 1Ds winning hands down. There is a question as to how much more information a 5080 dpi scanner gets out of a 35mm frame than a 4000 dpi scanner. I suspect that it's not enough of a difference to be significant. (None of the Minolta 5400 scans of actual images I've seen showed significant improvement over 4000 dpi scans, although the test chart images look a lot better.) David J. Littleboy [EMAIL PROTECTED] Tokyo, Japan I think this is probably true, due to the cutoff of the human eye and brain. Basically, for the size of prints most people produce, there probably isn't much to be gained by going above 4000 ppi scans, although I can see what's missing in a 4000 ppi scan versus the original image looked over with a loupe. However, I'd like to see what happens with a four foot wide poster print from a 35mm film scan (with a drum scanner) and a 9 MP digital image. The problem with the digicam image is that at the point that pixels become visible, then our eye starts to object due to the recognizable sharp and gridlike pixel edges. At that point, film grain (dye clouds) becomes more acceptable, because it is analog (random placement, size and overlap) which our eyes find more pleasing. Our world is full of analog visual noise, even our eyes produce it, so we learn to ignore it, but sharp edged square cornered patches of color are pretty obvious to us. It is the reason camouflage works so well, our eyes and brain don't register ill-defined edges of similar colors well. Art Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
Art, Austin, et al., Does a sensor 'average' the light falling on it, or does it use some other mathematical function? Bob Frost. - Original Message - From: Arthur Entlich [EMAIL PROTECTED] However, within its resolution, it accurately represents the average hue and luminosity that the film represents in that pixel location. Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
Arthur Entlich [EMAIL PROTECTED] writes: There is a question as to how much more information a 5080 dpi scanner gets out of a 35mm frame than a 4000 dpi scanner. I suspect that it's not enough of a difference to be significant. I think this is probably true, due to the cutoff of the human eye and brain. Basically, for the size of prints most people produce, there probably isn't much to be gained by going above 4000 ppi scans, although I can see what's missing in a 4000 ppi scan versus the original image looked over with a loupe. I've seen photomicrographs of Velvia and Kodachrome 25 that show a lot more than what a 4000 dpi scan gets. However, it's usually extremely high contrast subject matter (like test chartsg), and the grain is seriously ugly. It doesn't look (to me) as though that information is useful for pictorial photography. It might be useful for special effects and spying, I suppose. If you look at MTF charts, film begins to lose contrast pretty rapidly above 20 lp/mm and the contrast is way down at 40 lp/mm. Trying to get useful mileage out of such low contrast seems pretty hopeless. However, I'd like to see what happens with a four foot wide poster print from a 35mm film scan (with a drum scanner) and a 9 MP digital image. The problem with the digicam image is that at the point that pixels become visible, then our eye starts to object due to the recognizable sharp and gridlike pixel edges. There's no need to display pixels as squares at large sizes. Most digital images are taken through an antialiasing filter, and don't depend critically on individual pixels; that is, the highest frequency represented is usually 70% or so of the Nyquist frequency. So the area between pixels can be smoothed (blurred) by up to the pixel radius (if not more) with no loss of information, and no apparent pixelation, whatever size you print at. And dSLR images at ISO 100 are noise free. No grain, no pixels, no noise. At that point, film grain (dye clouds) becomes more acceptable, because it is analog (random placement, size and overlap) which our eyes find more pleasing. If you meander by the West exit of Shinjuku station here in Tokyo, you can see an 8 foot by 16 foot backlit mural. The grain's seriously ugly if you get close, but pictures that large are seriously cool, no matter how ugly. Inversely, there are occasionnal 30x40 advertising posters in the train stations that are clean and sharp even with my built-in 8x loupes (I'm grossly nearsighted and an incorrigible grain sniffer). I can't really speak to posters and murals. I don't like prints in the 16x20 to 30x40 range that I can't walk up to, so I wouldn't try to print any of the 645 I've done (Mamiya + Nikon 8000) at much over 12x16, 13x19 at most. But it sounds as though everyone who has ever printed a digital image at a riduculously large size has been extremely happy with the results, so I suspect that your intuition here is dead wrong. I suspect that the reason people are happy with large digital prints is that there's no noise/grain whatsoever. (I'd probably find it seriously irritating that there wasn't any detail to be seen, but that's me.) Our world is full of analog visual noise, even our eyes produce it, so we learn to ignore it, but sharp edged square cornered patches of color are pretty obvious to us. It is the reason camouflage works so well, our eyes and brain don't register ill-defined edges of similar colors well. Again, there's no reason to see pixels in larger digital images at all. David J. Littleboy [EMAIL PROTECTED] Tokyo, Japan Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
I'm very sure! The Pro 70 was the first consumer digicam with CFII and hence Microdrive compatibility, it's that old :-) It has a great lens and RAW capability so can dodge JPEG artifacts altogether. I know it's pushing the accepted wisdom, but people have mistaken the pictures for commercial posters so it's not just my opinion. And I meant 13x19, A3+ or B+ size - that was a typo. In article [EMAIL PROTECTED], [EMAIL PROTECTED] (LAURIE SOLOMON) wrote: I've produced very acceptable 13x9s from a 1.68 megapixel camera, the Canon Pro 70. Are you sure it is 1.68 megapixels? That is so low that I doubt they are even selling digital cameras with that few megapixel capacity. As for what is or is not very acceptible depends subjectively on one's tastes and standards; besides 13x9 is a somewhat smaller image than a 13x19, although 13x9 may be pushing the envelope for a 1-2 megapixel camera since the typical wisdom is that you need at least 3 megapixels to produce a satisfactory 8x10. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of [EMAIL PROTECTED] Sent: Tuesday, October 21, 2003 11:55 AM To: [EMAIL PROTECTED] Subject: [filmscanners] Re: Pixels and Prints I've produced very acceptable 13x9s from a 1.68 megapixel camera, the Canon Pro 70. Yes, when you get up close you can see staircasing from the lack of resolution, but in practice you don't examine big pictures close up. And for me the complete absence of film grain makes all the difference. In article [EMAIL PROTECTED], [EMAIL PROTECTED] () wrote: I suspect I will 'go digital' sometime in the next year or two. My question regards what type of print output quality I can expect from digital. I print on an Epson 2200 at sizes of up to 13x19 inches. In reality, I tend to leave an inch margin or so around the image, so lets say an image size of 11x17 inches. Conventional teaching with scans (and I suppose that this could be part of the answer..that the conventional holds with scans but not direct digital acquisition) is that for critical sharpness you should be able to send 300ppi to the printer. Say this is overkill and you really only need 250 ppi. By my calculations you would still need 11 megapixels fo an 11x17 image at 250ppi. Yet everyone raves at the output of even the Canon 10D at significantly less resolution. So is the conventional teaching incorrect when it comes to direct digital capture? Perhaps more importantly, how many megapixels are needed for an extremely sharp 11x17 inch print? I realize there are other benefits to digital capture as it translates to printing, such as lack of grain, but sharpness is quite important to me as well. I would appreciate any help in how to look at this as I think about getting a digital body. Right now I am using a 1V and a Polaroid Sprintscan 4000 Plus. A DS1 at 14 or so megapixels and full frame sensor is way too expensive for me...but if a new Canon EOS 3 type digital body were to come out I could see spending up to $2500 or so. Howard Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
Hi David, Because that's a different question. Someone argued that scanners produce better quality pixels because they measure all RGB, and I'm pointing out that this is wrong because scanned pixels are, in fact, worse than digital camera pixels. It's not wrong. If you are talking image fidelity, then it depends on what aspect of image fidelity is more important to you. CLEARLY the scanned pixel has higher color fidelity...and it may in fact have higher image detail fidelity as well... Even if the digicam image is sharper, sharpness may not mean higher image fidelity. so the interpolated pixels cheap shot is just that, a cheap shot. It's not a cheap shot, it's a fact, like it or not. If you consider the minimum dpi for acceptable print to be a measure of (the inverse of) an imaging technology's pixel quality, that raises the question of what is the parameter that limits that minimum dpi. It may be that it's chrominance resolution that limits dSLR images and luminance resolution that limits scanned image. You may very well be correct, I'd have to think about it. Again, I'm not the one comparing pixel-for-pixel; Me either...but someone brought it up, and I believe it's a useless comparison, as pixels have no relative dimension between images. and arguing that you have to downsample scanned images to get comparable pixels as measured by equivalent print quality. I agree. My best estimate is that 4000 dpi scans of Fuji 100F films downsampled to 2400 dpi turn into close to 10D quality. But...that's what I say is simply wrong, as a general statement. You MAY have an example that shows that as true, but that doesn't make it hold true for every example, variables being development, scanner and scanner operator. There are lots of people who come up with 9MP or so as the digital equivalent of 35. And there's a lot who come up with 16M, and 24M and 96M etc. It just isn't as simple as assigning a number. It's like saying, as a general statement, a Range Rover is better than a Porsche...in some aspects, yes, in some no, and it very much so depends on what aspect of an aspect is important to you. Regards, Austin Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
Ok, Paul. I do concur with your conclusion; and in practice, do what you suggest. From a theoretical point of view, I was just curious about the answer to the question given that so many in the discussion were arguing that if one sent the printer a file with less than its native resolution the printer would perform an interpolation using nearest neighbor techniques which would lower the quality of the output but did not mention the effect of the oposite case where one sent a file that had a resoution higher than the printer's native resolution. Thus, leaving open the question as to which theoretically would be the best option to take if one were to have a choice - e.g., letting the printer upsample to its native resolution or downsample to its native resolution. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Paul D. DeRocco Sent: Thursday, October 23, 2003 12:09 AM To: [EMAIL PROTECTED] Subject: [filmscanners] RE: Pixels and Prints From: LAURIE SOLOMON We may be miscommunicating. The native optical resolution of my Umax PowerLook III is 1200 ppi and for my film scanner around 2780 ppi for 35mm and 1100 for 120 films. If, for the sake of the argument, I want the size of the image to be 1:1 at those resolutions, I would be sending the printer a file whose resolution is more than the printer's native resolution, which means that the printer would be downsampling the file without any extra effort at altering the resolution on my part. Thus my question is it preferable to send the printer images whose unaltered native resolutions are higher than the printer's native resolution of 720/360 ppi or to send the printer images whose unaltered native resolutions are lower than the printer's native resolution of 720/360 ppi. In practice, I think it's a tangled mass of relatively unimportant trade-offs, with no clear answer. Scanning at high resolution reduces the danger of aliasing in the scanner, but increases the danger of aliasing in the printer. The best would be to scan at the highest resolution, and then use software with a good resampling algorithm to resample to the optimum resolution of the printer, or some integer submultiple. -- Ciao, Paul D. DeRocco Paulmailto:[EMAIL PROTECTED] Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body --- Incoming mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.528 / Virus Database: 324 - Release Date: 10/16/2003 --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.528 / Virus Database: 324 - Release Date: 10/16/2003 Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
I'm curious what your ppi is when you print to that 13 x 19? It's got to be in the low 100's. -Bill I'm very sure! The Pro 70 was the first consumer digicam with CFII and hence Microdrive compatibility, it's that old :-) It has a great lens and RAW capability so can dodge JPEG artifacts altogether. I know it's pushing the accepted wisdom, but people have mistaken the pictures for commercial posters so it's not just my opinion. And I meant 13x19, A3+ or B+ size - that was a typo. In article [EMAIL PROTECTED], [EMAIL PROTECTED] (LAURIE SOLOMON) wrote: I've produced very acceptable 13x9s from a 1.68 megapixel camera, the Canon Pro 70. Are you sure it is 1.68 megapixels? That is so low that I doubt they are even selling digital cameras with that few megapixel capacity. As for what is or is not very acceptible depends subjectively on one's tastes and standards; besides 13x9 is a somewhat smaller image than a 13x19, although 13x9 may be pushing the envelope for a 1-2 megapixel camera since the typical wisdom is that you need at least 3 megapixels to produce a satisfactory 8x10. Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
I'm very sure! The Pro 70 was the first consumer digicam with CFII and hence Microdrive compatibility, it's that old :-) It has a great lens and RAW capability so can dodge JPEG artifacts altogether. I know it's pushing the accepted wisdom, but people have mistaken the pictures for commercial posters so it's not just my opinion. And I meant 13x19, A3+ or B+ size - that was a typo. In article [EMAIL PROTECTED], [EMAIL PROTECTED] (LAURIE SOLOMON) wrote: I've produced very acceptable 13x9s from a 1.68 megapixel camera, the Canon Pro 70. Are you sure it is 1.68 megapixels? That is so low that I doubt they are even selling digital cameras with that few megapixel capacity. As for what is or is not very acceptible depends subjectively on one's tastes and standards; besides 13x9 is a somewhat smaller image than a 13x19, although 13x9 may be pushing the envelope for a 1-2 megapixel camera since the typical wisdom is that you need at least 3 megapixels to produce a satisfactory 8x10. I just have to weigh in on this. Even the current crop of 6M+ megapixel cameras barely produce acceptable 13 x 19 prints from unrezzed data. So a 1.68M pixel camera for a 13 x 19 image is not pushing the envelope, it's simply not believable. There simply is not enough data there, by a factor of about 4 to produce an acceptable 13 x 19 print. That is, if we're talking inches. If you mean some other unit of measure, that's a different story. A 1.68 M pixel camera will have a file that is ~ 1.6k x 1k. And, 1.6k over 19 inches is only 84 PPI to the printer, and that will give you very pixelated printouts. Now, if you rez up the images to get more PPI to the printer, you can eliminate the pixelated look...but the fidelity of the image data is questionable. You can't create detail where detail didn't exist in the original file in the first place. Though the image may be sharp, and may look good standing alone, so does a comic strip... It all depends on what you are looking for. If you want a detailed large image, a 1.68M pixel image simply will not do. If you want simply a graphical representation of the major outlines of the image, it will do. Regards, Austin Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
This didn't start out as a film vs digital comparison but a scanned film vs digital one. So both images have hard pixels. In article [EMAIL PROTECTED], [EMAIL PROTECTED] (Arthur Entlich) wrote: David J. Littleboy wrote: The question is what the cutoff point is. It looks to me that 35mm film is worth about 9MP, not 24MP. Most people comparing the 1Ds to 35mm film find the 1Ds winning hands down. There is a question as to how much more information a 5080 dpi scanner gets out of a 35mm frame than a 4000 dpi scanner. I suspect that it's not enough of a difference to be significant. (None of the Minolta 5400 scans of actual images I've seen showed significant improvement over 4000 dpi scans, although the test chart images look a lot better.) David J. Littleboy [EMAIL PROTECTED] Tokyo, Japan I think this is probably true, due to the cutoff of the human eye and brain. Basically, for the size of prints most people produce, there probably isn't much to be gained by going above 4000 ppi scans, although I can see what's missing in a 4000 ppi scan versus the original image looked over with a loupe. However, I'd like to see what happens with a four foot wide poster print from a 35mm film scan (with a drum scanner) and a 9 MP digital image. The problem with the digicam image is that at the point that pixels become visible, then our eye starts to object due to the recognizable sharp and gridlike pixel edges. At that point, film grain (dye clouds) becomes more acceptable, because it is analog (random placement, size and overlap) which our eyes find more pleasing. Our world is full of analog visual noise, even our eyes produce it, so we learn to ignore it, but sharp edged square cornered patches of color are pretty obvious to us. It is the reason camouflage works so well, our eyes and brain don't register ill-defined edges of similar colors well. Art Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
From: Bob Frost Does a sensor 'average' the light falling on it, or does it use some other mathematical function? Yes. However, there are spaces between the sensor elements, and it's desireable to capture the light that would fall there. In addition, you don't want the capture area of each sensor to have sharp edges--that leads to aliasing on fine patterns. Therefore, a good digicam sensor will have a diffuser over it, so that the capture area of the elements will be essentially overlapping fuzzy blobs instead of sharply defined circles or squares. The function that defines the intensity versus distance-off-center is essentially a finite impulse response filter that is applied to the image. -- Ciao, Paul D. DeRocco Paulmailto:[EMAIL PROTECTED] Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
Laurie, I thought I had read somewhere that if you send images to the Epson driver with dpi that are larger than its native dpi (360/720) it simply discards rows of pixels as scanners often do, rather than downsample them by any interpolation method. Bob Frost. - Original Message - From: LAURIE SOLOMON [EMAIL PROTECTED] I do concur with your conclusion; and in practice, do what you suggest. From a theoretical point of view, I was just curious about the answer to the question given that so many in the discussion were arguing that if one sent the printer a file with less than its native resolution the printer would perform an interpolation using nearest neighbor techniques which would lower the quality of the output but did not mention the effect of the oposite case where one sent a file that had a resoution higher than the printer's native resolution. Thus, leaving open the question as to which theoretically would be the best option to take if one were to have a choice - e.g., letting the printer upsample to its native resolution or downsample to its native resolution. Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
So a 1.68M pixel camera for a 13 x 19 image is not pushing the envelope, it's simply not believable. Just for the record, I did not say that a 1.68M pixel camera for a 13 x 19 image is pushing the envelope: I said that it was pushing the envelope to print a 13 x 9 inch print from a 1-2 megapixel camera capture with or without interpolation since conventional wisdom suggests that you would need a 3 megapixel camera to produce an satisfactory 8x10 inch print (I did take the typo to be the size and was not referring to the 13 x 19 dimension that was really inteded, which I agree with you would not be realistic and would be beyond pushing the envelope). [EMAIL PROTECTED] wrote: I'm very sure! The Pro 70 was the first consumer digicam with CFII and hence Microdrive compatibility, it's that old :-) It has a great lens and RAW capability so can dodge JPEG artifacts altogether. I know it's pushing the accepted wisdom, but people have mistaken the pictures for commercial posters so it's not just my opinion. And I meant 13x19, A3+ or B+ size - that was a typo. In article [EMAIL PROTECTED], [EMAIL PROTECTED] (LAURIE SOLOMON) wrote: I've produced very acceptable 13x9s from a 1.68 megapixel camera, the Canon Pro 70. Are you sure it is 1.68 megapixels? That is so low that I doubt they are even selling digital cameras with that few megapixel capacity. As for what is or is not very acceptible depends subjectively on one's tastes and standards; besides 13x9 is a somewhat smaller image than a 13x19, although 13x9 may be pushing the envelope for a 1-2 megapixel camera since the typical wisdom is that you need at least 3 megapixels to produce a satisfactory 8x10. I just have to weigh in on this. Even the current crop of 6M+ megapixel cameras barely produce acceptable 13 x 19 prints from unrezzed data. So a 1.68M pixel camera for a 13 x 19 image is not pushing the envelope, it's simply not believable. There simply is not enough data there, by a factor of about 4 to produce an acceptable 13 x 19 print. That is, if we're talking inches. If you mean some other unit of measure, that's a different story. A 1.68 M pixel camera will have a file that is ~ 1.6k x 1k. And, 1.6k over 19 inches is only 84 PPI to the printer, and that will give you very pixelated printouts. Now, if you rez up the images to get more PPI to the printer, you can eliminate the pixelated look...but the fidelity of the image data is questionable. You can't create detail where detail didn't exist in the original file in the first place. Though the image may be sharp, and may look good standing alone, so does a comic strip... It all depends on what you are looking for. If you want a detailed large image, a 1.68M pixel image simply will not do. If you want simply a graphical representation of the major outlines of the image, it will do. Regards, Austin -- -- Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body --- Incoming mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.525 / Virus Database: 322 - Release Date: 10/9/2003 --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.525 / Virus Database: 322 - Release Date: 10/9/2003 Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
Austin, Surely you can; it just isn't 'original' detail. But to anyone who hadn't seen the original detail, it might look just as good. After all, people pay millions for artists' representations of original detail, so why shouldn't a digicam representation of original detail make a good picture. It might not be an 'accurate' record, but then neither is the painting, and I doubt if 'accurate record' pictures are what turn most people on. They clearly are what turns you on, but you are unusual I suggest!! Bob Frost. - Original Message - From: Austin Franklin [EMAIL PROTECTED] You can't create detail where detail didn't exist in the original file in the first place. Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
Hi Bob, Of course, you can make up anything in an image that you want...you can put a soldier pointing a gun at a man with a child, but what's important is that anything you simply make up isn't original. I don't know of any programs that create new detail (automatically that is) where none existed before...do you? Does GF do that? Basically, this is the same argument as to how much you can PhotoShop an image before it isn't really representative of the original recording. Some argue that BW isn't really representative of an original, and is actually an abstract. I do in fact like to keep the fidelity of the image as high as possible, that, to me, is what photography is about...as is audio. Obviously, some people like to PS their images...some more than others...to each his own...but I do believe that photography (at least labeled as photography) is supposed to be representative of reality (IOW, maintain the highest fidelity), and though I completely accept people manipulating their images, and calling it art, I think it should be labeled as such...and adding detail to an image that simply didn't exist in the original representation of the image is a manipulation of the recording of the image. I'm not against it, just in people calling it photography ;-) Regards, Austin Surely you can; it just isn't 'original' detail. But to anyone who hadn't seen the original detail, it might look just as good. After all, people pay millions for artists' representations of original detail, so why shouldn't a digicam representation of original detail make a good picture. It might not be an 'accurate' record, but then neither is the painting, and I doubt if 'accurate record' pictures are what turn most people on. They clearly are what turns you on, but you are unusual I suggest!! Bob Frost. - Original Message - From: Austin Franklin [EMAIL PROTECTED] You can't create detail where detail didn't exist in the original file in the first place. -- -- Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
And just where would you put Ansel Adam's highly manipulated images in this scheme of things? Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
Hi Austin, And just where would you put Ansel Adam's highly manipulated images in this scheme of things? Er, as highly manipulated images ;-) Regards, Austin Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
I already pointed out that I was talking about A3+ pictures, so the size is in inches. I also didn't use any pre-print rescaling as I still believe the printer driver has the best information available to interpolate with knowledge of where it is going to dither. Also you haven't specified what kind of subject you're talking about and TBF neither did I. I'm not even going to claim that my standards of acceptability match yours, this is so subjective. But I know what I saw and it completely changed my view of how the accepted minima can be regarded. And to suggest that all I'd end up with is a cartoon is absurd. In article [EMAIL PROTECTED], [EMAIL PROTECTED] (Austin Franklin) wrote: I just have to weigh in on this. Even the current crop of 6M+ megapixel cameras barely produce acceptable 13 x 19 prints from unrezzed data. So a 1.68M pixel camera for a 13 x 19 image is not pushing the envelope, it's simply not believable. There simply is not enough data there, by a factor of about 4 to produce an acceptable 13 x 19 print. That is, if we're talking inches. If you mean some other unit of measure, that's a different story. A 1.68 M pixel camera will have a file that is ~ 1.6k x 1k. And, 1.6k over 19 inches is only 84 PPI to the printer, and that will give you very pixelated printouts. Now, if you rez up the images to get more PPI to the printer, you can eliminate the pixelated look...but the fidelity of the image data is questionable. You can't create detail where detail didn't exist in the original file in the first place. Though the image may be sharp, and may look good standing alone, so does a comic strip... It all depends on what you are looking for. If you want a detailed large image, a 1.68M pixel image simply will not do. If you want simply a graphical representation of the major outlines of the image, it will do. Regards, Austin Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
Bob, If true than I would think that this would be something important to know and play an important role in how one approaches things. I would have thought that to maintain quality output, they would have selected to design the printers to resample rather than merely discard pixels in an arbitrary or random manner. Surely, they use some sort of formula for determining what to discard and what to keep. [EMAIL PROTECTED] wrote: Laurie, I thought I had read somewhere that if you send images to the Epson driver with dpi that are larger than its native dpi (360/720) it simply discards rows of pixels as scanners often do, rather than downsample them by any interpolation method. Bob Frost. - Original Message - From: LAURIE SOLOMON [EMAIL PROTECTED] I do concur with your conclusion; and in practice, do what you suggest. From a theoretical point of view, I was just curious about the answer to the question given that so many in the discussion were arguing that if one sent the printer a file with less than its native resolution the printer would perform an interpolation using nearest neighbor techniques which would lower the quality of the output but did not mention the effect of the oposite case where one sent a file that had a resoution higher than the printer's native resolution. Thus, leaving open the question as to which theoretically would be the best option to take if one were to have a choice - e.g., letting the printer upsample to its native resolution or downsample to its native resolution. -- -- Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body --- Incoming mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.525 / Virus Database: 322 - Release Date: 10/9/2003 --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.525 / Virus Database: 322 - Release Date: 10/9/2003 Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
Hi all Good question Laurie. I see you have asked it several times. The one about what the printer does with the binary data you send it. I vaguely recalled seeing this explained, so it didn't take long to find this link http://www.ddisoftware.com/qimage/quality/ The Lanczos interpolation really does seem to make a difference. Darrell -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Laurie Solomon Sent: Thursday, October 23, 2003 5:50 PM To: [EMAIL PROTECTED] Subject: [filmscanners] RE: Pixels and Prints Bob, If true than I would think that this would be something important to know and play an important role in how one approaches things. I would have thought that to maintain quality output, they would have selected to design the printers to resample rather than merely discard pixels in an arbitrary or random manner. Surely, they use some sort of formula for determining what to discard and what to keep. [EMAIL PROTECTED] wrote: Laurie, I thought I had read somewhere that if you send images to the Epson driver with dpi that are larger than its native dpi (360/720) it simply discards rows of pixels as scanners often do, rather than downsample them by any interpolation method. Bob Frost. - Original Message - From: LAURIE SOLOMON [EMAIL PROTECTED] I do concur with your conclusion; and in practice, do what you suggest. From a theoretical point of view, I was just curious about the answer to the question given that so many in the discussion were arguing that if one sent the printer a file with less than its native resolution the printer would perform an interpolation using nearest neighbor techniques which would lower the quality of the output but did not mention the effect of the oposite case where one sent a file that had a resoution higher than the printer's native resolution. Thus, leaving open the question as to which theoretically would be the best option to take if one were to have a choice - e.g., letting the printer upsample to its native resolution or downsample to its native resolution. -- -- Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body --- Incoming mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.525 / Virus Database: 322 - Release Date: 10/9/2003 --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.525 / Virus Database: 322 - Release Date: 10/9/2003 Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
Austin, I know, but I've lapsed into using the same terms as most other people (you excepted). It gets painful banging your head against a brick wall after a while. Same with metamerism; hardly anyone uses it correctly, so after a while you just 'go with the flow'. Bob Frost. - Original Message - From: Austin Franklin [EMAIL PROTECTED] Just a minor clarification...both of you really mean PPI, as in pixels per inch, which is what you send to the printer...you don't send dots to the printer, the printer, though, in our case, prints dots. Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
All the more reason to insure that your P/D converter card is in tip top shape. Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
Karl, I think you've missed my point. All images, whatever their ppi (correct this time, Austin), printed on Epson inkjets are upsampled by the Epson driver, unless they are already at the ppi which the driver requires (360ppi for wideformat printers and 720ppi for desktop printers) whether you like it or not. So yes, upsampling may always result in some loss, but there is no way of preventing it other than sending your image at 360 or 720 depending on your printer. Since I understand that the printer driver uses Nearest Neighbour resampling - the poorest upsampling method according to many - it might be preferable to do the upsampling yourself with a better algorithm such as Vector, Lanczos, Bicubic, etc and avoid having the printer driver do it with NN. People who think they are avoiding upsampling by sending their image to the printer as it comes are deluding themselves; the printer driver will upsample it to 360 or 720ppi, come what may. And if sharpening is best done after everything else, including upsampling, by doing the upsampling to 360 or 720 your self you can then do the sharpening as the last thing. Otherwise you have to oversharpen in order to allow for the driver upsampling lessening the effect. Bob Frost. - Original Message - From: KARL SCHULMEISTERS [EMAIL PROTECTED] Upsampling always results in some loss - it might be artifacts, it might be loss of tonal gradation. Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
Hi Bob, I think you've missed my point. All images, whatever their ppi (correct this time, Austin) I'm flattered, Bob ;-) , printed on Epson inkjets are upsampled by the Epson driver, unless they are already at the ppi which the driver requires (360ppi for wideformat printers and 720ppi for desktop printers) whether you like it or not. So yes, upsampling may always result in some loss, but there is no way of preventing it other than sending your image at 360 or 720 depending on your printer. Since I understand that the printer driver uses Nearest Neighbour resampling - the poorest upsampling method according to many - it might be preferable to do the upsampling yourself with a better algorithm such as Vector, Lanczos, Bicubic, etc and avoid having the printer driver do it with NN. An excellent point, one I'd like to hear more results from. I have heard, but have not tried, of people doing this. The claims I heard were that the image was improved...but of course, that's subjective, and will be quite image dependant. People who think they are avoiding upsampling by sending their image to the printer as it comes are deluding themselves; the printer driver will upsample it to 360 or 720ppi, come what may. One caveat...if someone is using a non-standard driver, like the Piezo BW driver. Regards, Austin Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
O.K., you win. I had to look that one up. :-0 Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
I've produced very acceptable 13x9s from a 1.68 megapixel camera, the Canon Pro 70. Are you sure it is 1.68 megapixels? That is so low that I doubt they are even selling digital cameras with that few megapixel capacity. As for what is or is not very acceptible depends subjectively on one's tastes and standards; besides 13x9 is a somewhat smaller image than a 13x19, although 13x9 may be pushing the envelope for a 1-2 megapixel camera since the typical wisdom is that you need at least 3 megapixels to produce a satisfactory 8x10. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of [EMAIL PROTECTED] Sent: Tuesday, October 21, 2003 11:55 AM To: [EMAIL PROTECTED] Subject: [filmscanners] Re: Pixels and Prints I've produced very acceptable 13x9s from a 1.68 megapixel camera, the Canon Pro 70. Yes, when you get up close you can see staircasing from the lack of resolution, but in practice you don't examine big pictures close up. And for me the complete absence of film grain makes all the difference. In article [EMAIL PROTECTED], [EMAIL PROTECTED] () wrote: I suspect I will 'go digital' sometime in the next year or two. My question regards what type of print output quality I can expect from digital. I print on an Epson 2200 at sizes of up to 13x19 inches. In reality, I tend to leave an inch margin or so around the image, so lets say an image size of 11x17 inches. Conventional teaching with scans (and I suppose that this could be part of the answer..that the conventional holds with scans but not direct digital acquisition) is that for critical sharpness you should be able to send 300ppi to the printer. Say this is overkill and you really only need 250 ppi. By my calculations you would still need 11 megapixels fo an 11x17 image at 250ppi. Yet everyone raves at the output of even the Canon 10D at significantly less resolution. So is the conventional teaching incorrect when it comes to direct digital capture? Perhaps more importantly, how many megapixels are needed for an extremely sharp 11x17 inch print? I realize there are other benefits to digital capture as it translates to printing, such as lack of grain, but sharpness is quite important to me as well. I would appreciate any help in how to look at this as I think about getting a digital body. Right now I am using a 1V and a Polaroid Sprintscan 4000 Plus. A DS1 at 14 or so megapixels and full frame sensor is way too expensive for me...but if a new Canon EOS 3 type digital body were to come out I could see spending up to $2500 or so. Howard Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body --- Incoming mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.528 / Virus Database: 324 - Release Date: 10/16/2003 --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.528 / Virus Database: 324 - Release Date: 10/16/2003 Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
To Bob, Austin, and others, Based on the discussion, an interesting question is raised. Since 720 ppi is needed by the printer driver for a desktop printer and 360 ppi for a wide format printer, is it better to send the printer files with less than 320 or 720 ppi and let it upsample the image or to send it files with more than 320 or 720 ppi and let the printer driver downsample them - leaving aside the option of doing such resampling prior to sending the file to the printer? -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Bob Frost Sent: Tuesday, October 21, 2003 9:02 AM To: [EMAIL PROTECTED] Subject: [filmscanners] Re: Pixels and Prints Eugene, 240 dpi is not all that is needed, because the Epson driver upsamples that (or any other dpi you send it) to 720 dpi (desktop printers), using Nearest Neighbour type upsampling. So 720 dpi is what is needed by the driver. The question is can you get better results by upsampling to 720dpi yourself (using QI for example that upsamples with various superior methods - bicubic, lanczos, vector, etc). You seem to be suggesting that you can't, but others suggest you can. Bob Frost. - Original Message - From: Eugene A La Lancette PhD MD [EMAIL PROTECTED] 240 dpi is all that is needed. Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body --- Incoming mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.528 / Virus Database: 324 - Release Date: 10/16/2003 --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.528 / Virus Database: 324 - Release Date: 10/16/2003 Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
From: LAURIE SOLOMON Based on the discussion, an interesting question is raised. Since 720 ppi is needed by the printer driver for a desktop printer and 360 ppi for a wide format printer, is it better to send the printer files with less than 320 or 720 ppi and let it upsample the image or to send it files with more than 320 or 720 ppi and let the printer driver downsample them - leaving aside the option of doing such resampling prior to sending the file to the printer? I don't see how you'd be faced with this choice unless you had decided to explicitly resample before printing. In this case, it would make sense to choose the next highest resolution that divides evenly into the printer's natural resolution, to avoid aliasing. -- Ciao, Paul D. DeRocco Paulmailto:[EMAIL PROTECTED] Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
Of course each pixel of a scanned film has all three colours faithfully reproduced. The interesting question though is what that pixels's actual colour was? Unlike a camera, a film scan records something that has already been sampled into RGB, that's what film does! Yes the film grain is much smaller, and randomly scattered to boot. Sample aliasing means that each scanned pixel overlaps a number of film grain dye images, each an individual R G or B. So the pixel itself is effectively just an average like a Bayer filter pixel quad is an average. So it seems to me that there is no real moral high ground there, film scanning is just as much an averaging process as a Bayer camera. In article [EMAIL PROTECTED], [EMAIL PROTECTED] (Austin Franklin) wrote: Roger, So what if it's second generation? Unless you can analyze the fidelity of it to make claims from, that's simply an argument that has no teeth. Fact is, digicam pixels have some %66 of the red, %66 of the blue and %50 of the green data interpolated. Scanned film data does not. It has all three color values as original information. So, second generation or not, the fidelity (which is what is important) of the data from scanned film far outweighs digicam data of the same resolution. How good the scanned data is, depends a lot on how good the original film image is, as well as how good the scanner/operator is. Not all scanners scan 4000 PPI the same. Even if you recorded Ozzie live with your 8 track tape recorder, my nth generation CD will have a far higher fidelity. Regards, Austin Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
[EMAIL PROTECTED] writes: Of course each pixel of a scanned film has all three colours faithfully reproduced. The interesting question though is what that pixels's actual colour was? Unlike a camera, a film scan records something that has already been sampled into RGB, that's what film does! Yes the film grain is much smaller, and randomly scattered to boot. Sample aliasing means that each scanned pixel overlaps a number of film grain dye images, each an individual R G or B. So the pixel itself is effectively just an average like a Bayer filter pixel quad is an average. So it seems to me that there is no real moral high ground there, film scanning is just as much an averaging process as a Bayer camera. Then there's the reality check of actually looking at film scans and actually looking at some digital camera images and seeing how they compare. If one actually did that, one would see that, on a pixel-for-pixel basis (that is, comparing the same number of pixels), film scans are incredibly poor, being soft and noisy. As I mentioned before, downsampling 4000 dpi scans of Fuji 100F slides to 60% results in images that are beginning to be similar quality to digital camera originals. David J. Littleboy [EMAIL PROTECTED] Tokyo, Japan Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
It is very simple Paul; if you scan an image or film frame at 1200 ppi or above and do not down sample in PS or another editing program but send it on to the printer, you will be faced with this choice. It is only if you DO resample downward in this case would you not be faced with the chouce. [EMAIL PROTECTED] wrote: From: LAURIE SOLOMON Based on the discussion, an interesting question is raised. Since 720 ppi is needed by the printer driver for a desktop printer and 360 ppi for a wide format printer, is it better to send the printer files with less than 320 or 720 ppi and let it upsample the image or to send it files with more than 320 or 720 ppi and let the printer driver downsample them - leaving aside the option of doing such resampling prior to sending the file to the printer? I don't see how you'd be faced with this choice unless you had decided to explicitly resample before printing. In this case, it would make sense to choose the next highest resolution that divides evenly into the printer's natural resolution, to avoid aliasing. --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.525 / Virus Database: 322 - Release Date: 10/9/2003 Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
Hi David, Then there's the reality check of actually looking at film scans and actually looking at some digital camera images and seeing how they compare. If one actually did that, one would see that, on a pixel-for-pixel basis (that is, comparing the same number of pixels), film scans are incredibly poor, being soft and noisy. As I mentioned before, downsampling 4000 dpi scans of Fuji 100F slides to 60% results in images that are beginning to be similar quality to digital camera originals. That depends on a LOT of things. The film, the development and the scanner. I have seen extreme differences between high end film, excellent exposure/development and using a very good scanner...much less a high end scanner...vs...most decent films scanned on a con/prosumer based scanner. I have compared scans from my scanner (Leaf45, which scans 35mm at 5080) and different digital cameras (Leaf Lumina, which is a TRUE RGB digital camera in that it gives %100 of the color information per pixel...as well as D30, D60, Hasselblad digital backs etc. The ONLY digital cameras that come close to my best film scans are the 7k x 7k Hasselblad scanning back (which actually beats most film, but is useless in the real world only in the studio) and the Lumina comes close, but not quite (which is a 2k x 3k scanning camera). The others, though good, simply don't compare to a high end film scan. Then there is the issue of the Bayer pattern fidelity...even though the digicam images look sharper, sharpness is not the only criteria for an image. In fact, it is typically a false indicator IMO. Though, some people believe it looks good, in fact, it really has nothing to do with image fidelity. A two pixel camera will give you a sharp image... I don't think the generalizations I've seen here are valid as generalizations. Certainly, what you see is what you see, but that doesn't mean it holds true for all situations. Because one uses a Holga, doesn't mean all medium format images are no better than the images from an SX-70 ;-) Regards, Austin Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
From: Laurie Solomon It is very simple Paul; if you scan an image or film frame at 1200 ppi or above and do not down sample in PS or another editing program but send it on to the printer, you will be faced with this choice. It is only if you DO resample downward in this case would you not be faced with the chouce. But if you scan at a particular resolution, and you want the print to be a certain size, then you've already determined whether you have less or more resolution than the printer's native 720ppi resolution. You can of course change the scan resolution, but in most scanners all that does is another software resampling, so whether that's good or bad depends upon the quality of the resampling function. My approach has always been to scan at the native resolution of the scanner, edit and crop to my heart's content, and then, if I suspect aliasing might be a problem, upsample in PS to the next lower submultiple of 720. -- Ciao, Paul D. DeRocco Paulmailto:[EMAIL PROTECTED] Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
Austin Franklin [EMAIL PROTECTED] writes: Then there's the reality check of actually looking at film scans and actually looking at some digital camera images and seeing how they compare. If one actually did that, one would see that, on a pixel-for-pixel basis (that is, comparing the same number of pixels), film scans are incredibly poor, being soft and noisy. As I mentioned before, downsampling 4000 dpi scans of Fuji 100F slides to 60% results in images that are beginning to be similar quality to digital camera originals. That depends on a LOT of things. The film, the development and the scanner. I have seen extreme differences between high end film, excellent exposure/development and using a very good scanner...much less a high end scanner...vs...most decent films scanned on a con/prosumer based scanner. I have compared scans from my scanner (Leaf45, which scans 35mm at 5080) and different digital cameras (Leaf Lumina, which is a TRUE RGB digital camera in that it gives %100 of the color information per pixel...as well as D30, D60, Hasselblad digital backs etc. The ONLY digital cameras that come close to my best film scans are the 7k x 7k Hasselblad scanning back (which actually beats most film, but is useless in the real world only in the studio) and the Lumina comes close, but not quite (which is a 2k x 3k scanning camera). I think you've misunderstood what I've said. Take a 900 x 900 pixel crop from your 5080 dpi scan and print it at 3x3 inches. Take a 900x900 crop from a 10D image and print it at 3x3 inches. Which looks better? Since that's a 16x enlargement from film, it's going to look pretty poor. But 10D images look very good printed at 300 dpi. So the argument that scanned pixels are, on an individual basis, in any way better than 10D pixels, strikes me as seriously problematic. David J. Littleboy [EMAIL PROTECTED] Tokyo, Japan Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
On Wed, 22 Oct 2003 09:29:05 -0400, Austin Franklin wrote: An excellent point, one I'd like to hear more results from. I have heard, but have not tried, of people doing this. The claims I heard were that the image was improved...but of course, that's subjective, and will be quite image dependant. In my thoroughly subjective and highly non-systematic tests, I seem to get better results with higher resolution up to about 700 or 750 ppi sent to the printer. I'm printing to an Epson Stylus Photo 820 using the Epson driver. I am not examining the prints with a loupe, just my Mark 1 Mod 0 eyeball. TTYL, DougF KG4LMZ -- Outgoing mail is certified Virus Free by Grisoft's AVG. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.528 / Virus Database: 324 - Release Date: 03-10-16 Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
I'm with Austin on this one... Yes, the scanner would be hard pressed to fully accurately represent every grain (dye cloud) unless if was extremely high resolution. However, within its resolution, it accurately represents the average hue and luminosity that the film represents in that pixel location. The Bayer pattern doesn't average, it interpolates. It guesses the value based upon surrounding pixels, and it can be off a fair amount during transitions and drastic hue changes. Each location, each pixel, in the film scanner represents an averaging of the pixel dimensions of the film information it represents. Not so with Bayer patterns. Any one pixel only knows one color component (R,G or B) and luminosity of that area, nothing more. All other information is determined by assumptions about the neighboring pixels values, which also lack information about the other component colors. 50% of the pixel captures in the Bayer Pattern have no knowledge of the red and blue component in their color. 25% have no true input for the red or green and 25% have no true input for the green and blue component. In other words, clearly 75% of the pixels do not have a defined red component and the same for blue. It's actually amazing that the concept works at all ;-) Every pixel on a film scanned image has all three color components accurately expressed within the limitation of its resolution. It literally samples every pixel it represents in all three component colors, averaging them within the area of that sample. The one advantage of the digital camera is that the capture media is identical to the sampling in X/Y dimension, so there is no averaging of information within the sampling area. In its native resolution, one CCD sensor equals one pixel dimension, and therefore the color and luminosity information within the area is already averaged by the sensor, from the image projected on it by the lens. where grain (dye clouds) is random is shape, location and overlap. Art PS: I'm not sure why Austin and I are coming up with different percentages on the red and blue accuracy values. He indicates 66%, and I'm coming up with 75%. I'll defer to him, because this is his area of expertise, but I don't understand what it is I'm doing wrong in my thinking. As I understand it, the Bayer pattern uses a system with 50% green, 25% red and 25% blue sensitive sensors (using color separation filters). Since neither the green pixels (50%) nor can the blue (25%) can accurately detect the red component, doesn't that mean 75% of the the locations are interpolated for the red component? [EMAIL PROTECTED] wrote: Of course each pixel of a scanned film has all three colours faithfully reproduced. The interesting question though is what that pixels's actual colour was? Unlike a camera, a film scan records something that has already been sampled into RGB, that's what film does! Yes the film grain is much smaller, and randomly scattered to boot. Sample aliasing means that each scanned pixel overlaps a number of film grain dye images, each an individual R G or B. So the pixel itself is effectively just an average like a Bayer filter pixel quad is an average. So it seems to me that there is no real moral high ground there, film scanning is just as much an averaging process as a Bayer camera. In article [EMAIL PROTECTED], [EMAIL PROTECTED] (Austin Franklin) wrote: Roger, So what if it's second generation? Unless you can analyze the fidelity of it to make claims from, that's simply an argument that has no teeth. Fact is, digicam pixels have some %66 of the red, %66 of the blue and %50 of the green data interpolated. Scanned film data does not. It has all three color values as original information. So, second generation or not, the fidelity (which is what is important) of the data from scanned film far outweighs digicam data of the same resolution. How good the scanned data is, depends a lot on how good the original film image is, as well as how good the scanner/operator is. Not all scanners scan 4000 PPI the same. Even if you recorded Ozzie live with your 8 track tape recorder, my nth generation CD will have a far higher fidelity. Regards, Austin Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
Hi David, I think you've misunderstood what I've said. Take a 900 x 900 pixel crop from your 5080 dpi scan and print it at 3x3 inches. Take a 900x900 crop from a 10D image and print it at 3x3 inches. Which looks better? That depends, and I am curious why you think that is of any value? If a 300 x 300 crop from a 10D represents 16x more area, why not compare actual area for area? You're making the arbitrary choice of sensor sizes/metrics here. The pixel area from one is not necessarily of equal value to the pixel area from another, and what the equality is, depends on how many pixels there are for the respective image. I could downsample my scanner to give me the exact same image area information as the 10D, and that information would contain complete color values, not interpolated pixels. So the argument that scanned pixels are, on an individual basis, in any way better than 10D pixels, strikes me as seriously problematic. But...the 10D doesn't really have pixels...it has sensors, and those sensors are in a Bayer pattern. The scanner has full color pixels, and the output of the scanner can be made to give you pixels that represent the same image information. Now, if you want to compare that (and why not, it's pixels for pixels, which is your metric, and IMO, a far better metric than the processed output of a digicam vs the raw output of a film scanner), then I guarantee you my 5080 DPI scanner will give me a FAR better looking image than the 10D will. Regards, Austin Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
Now wait a minute here... If I am not mistaken in one case you are taking a 900 x 900 pixel sample from a 3000 x 2000 pixel (approximately) dimensioned image. In the other case, you are taking the same 900 x 900 pixel section from a 5080 x 5080 (or there about) pixel image, which is considerably less total image information. If you are saying on a pixel per pixel basis (excluding resolution of the total image) that the Bayer patterned digicam image looks cleaner and better than the translated dye cloud (film) to squared pixels by scanning, then you'll get no argument from me. The digicam image is designed for the square pixelled format, and the translation takes place at the point the light hits the sensor, rather than going through the whole translation process, going from light, to photon chemical reactions to more (liquid) chemical reactions on randomly sized and positioned dots (grain/dye clouds) then reformatted to fit square pixels. So you'll get no argument from me there. The Bayer patterned image doesn't have the accuracy of color the film will (at the same resolution) and the film is obviously still resolution superior, even after scanning. Yes, once the digital cameras provide 4000 or 5000 ppi resolution, no question, it will look better (even if the color still won't be as accurate), but I think it's a way off financially. A decent film camera and some quality film still is a bit more affordable than 24 megapixel sensored digicams. Art David J. Littleboy wrote: Austin Franklin [EMAIL PROTECTED] writes: Then there's the reality check of actually looking at film scans and actually looking at some digital camera images and seeing how they compare. If one actually did that, one would see that, on a pixel-for-pixel basis (that is, comparing the same number of pixels), film scans are incredibly poor, being soft and noisy. As I mentioned before, downsampling 4000 dpi scans of Fuji 100F slides to 60% results in images that are beginning to be similar quality to digital camera originals. That depends on a LOT of things. The film, the development and the scanner. I have seen extreme differences between high end film, excellent exposure/development and using a very good scanner...much less a high end scanner...vs...most decent films scanned on a con/prosumer based scanner. I have compared scans from my scanner (Leaf45, which scans 35mm at 5080) and different digital cameras (Leaf Lumina, which is a TRUE RGB digital camera in that it gives %100 of the color information per pixel...as well as D30, D60, Hasselblad digital backs etc. The ONLY digital cameras that come close to my best film scans are the 7k x 7k Hasselblad scanning back (which actually beats most film, but is useless in the real world only in the studio) and the Lumina comes close, but not quite (which is a 2k x 3k scanning camera). I think you've misunderstood what I've said. Take a 900 x 900 pixel crop from your 5080 dpi scan and print it at 3x3 inches. Take a 900x900 crop from a 10D image and print it at 3x3 inches. Which looks better? Since that's a 16x enlargement from film, it's going to look pretty poor. But 10D images look very good printed at 300 dpi. So the argument that scanned pixels are, on an individual basis, in any way better than 10D pixels, strikes me as seriously problematic. David J. Littleboy [EMAIL PROTECTED] Tokyo, Japan Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
Arthur Entlich [EMAIL PROTECTED] writes: If I am not mistaken in one case you are taking a 900 x 900 pixel sample from a 3000 x 2000 pixel (approximately) dimensioned image. In the other case, you are taking the same 900 x 900 pixel section from a 5080 x 5080 (or there about) pixel image, which is considerably less total image information. Exactly. If you are saying on a pixel per pixel basis (excluding resolution of the total image) that the Bayer patterned digicam image looks cleaner and better than the translated dye cloud (film) to squared pixels by scanning, then you'll get no argument from me. ExactlyG. I was objecting to claims of the form my scanner produces 210 MP when your digital camera only produces 6MP. The digicam image is designed for the square pixelled format, and the translation takes place at the point the light hits the sensor, rather than going through the whole translation process, going from light, to photon chemical reactions to more (liquid) chemical reactions on randomly sized and positioned dots (grain/dye clouds) then reformatted to fit square pixels. So you'll get no argument from me there. The Bayer patterned image doesn't have the accuracy of color the film will (at the same resolution) and the film is obviously still resolution superior, even after scanning. The difference goes the other way if you look at film of the same area as the digital sensor. A 15x22 mm area of film printed at A4 (a 14x enlargement) is going to look pretty funky compared to a sharp 10D image. Yes, once the digital cameras provide 4000 or 5000 ppi resolution, no question, it will look better (even if the color still won't be as accurate), but I think it's a way off financially. A decent film camera and some quality film still is a bit more affordable than 24 megapixel sensored digicams. The question is what the cutoff point is. It looks to me that 35mm film is worth about 9MP, not 24MP. Most people comparing the 1Ds to 35mm film find the 1Ds winning hands down. There is a question as to how much more information a 5080 dpi scanner gets out of a 35mm frame than a 4000 dpi scanner. I suspect that it's not enough of a difference to be significant. (None of the Minolta 5400 scans of actual images I've seen showed significant improvement over 4000 dpi scans, although the test chart images look a lot better.) David J. Littleboy [EMAIL PROTECTED] Tokyo, Japan Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
Austin Franklin [EMAIL PROTECTED] writes: I think you've misunderstood what I've said. Take a 900 x 900 pixel crop from your 5080 dpi scan and print it at 3x3 inches. Take a 900x900 crop from a 10D image and print it at 3x3 inches. Which looks better? That depends, It doesn't depend. I've never seen a scan that was, on the pixel level, even close in quality to what the 10D produces. and I am curious why you think that is of any value? I'm curious too. I'm not the one making comments to the effect my scanner produces 210 MP when your digital camera only produces 6MP. If a 300 x 300 crop from a 10D represents 16x more area, why not compare actual area for area? Because that's a different question. Someone argued that scanners produce better quality pixels because they measure all RGB, and I'm pointing out that this is wrong because scanned pixels are, in fact, worse than digital camera pixels. (On an area for area basis, it seems digital wins, though. Most people comparing the 1Ds to 35mm find the 1Ds superior, and I suspect that even a 5080 dpi scan of a 15mm by 22.5mm section of film would look a lot worse at A4 than a 10D image would.) You're making the arbitrary choice of sensor sizes/metrics here. The pixel area from one is not necessarily of equal value to the pixel area from another, and what the equality is, depends on how many pixels there are for the respective image. I could downsample my scanner to give me the exact same image area information as the 10D, and that information would contain complete color values, not interpolated pixels. Bayer images have very close to the right ratio of luminance to color resolution for viewing by humans. If you print a Bayer image at a high enough dpi that you are satisfied with the detail, then the color resolution will be good enough as well, so the interpolated pixels cheap shot is just that, a cheap shot. If you print a scanned image at a high enough dpi that you are satisfied with the detail, then the color resolution will be insane overkill, unless your audience is Foveon equipped robots. Nothing wrong with insane overkill, it gets the job done. But it doesn't make a difference in the visual properties of the print. If you consider the minimum dpi for acceptable print to be a measure of (the inverse of) an imaging technology's pixel quality, that raises the question of what is the parameter that limits that minimum dpi. It may be that it's chrominance resolution that limits dSLR images and luminance resolution that limits scanned image. So the argument that scanned pixels are, on an individual basis, in any way better than 10D pixels, strikes me as seriously problematic. But...the 10D doesn't really have pixels...it has sensors, and those sensors are in a Bayer pattern. The scanner has full color pixels, and the output of the scanner can be made to give you pixels that represent the same image information. Now, if you want to compare that (and why not, it's pixels for pixels, which is your metric, and IMO, a far better metric than the processed output of a digicam vs the raw output of a film scanner), then I guarantee you my 5080 DPI scanner will give me a FAR better looking image than the 10D will. Again, I'm not the one comparing pixel-for-pixel; I'm _objecting_ to pixel-for-pixel comparisons, pointing out that it's a dizzy comparison, and arguing that you have to downsample scanned images to get comparable pixels as measured by equivalent print quality. My best estimate is that 4000 dpi scans of Fuji 100F films downsampled to 2400 dpi turn into close to 10D quality. Maybe the better 35mm lenses are sharper than my Mamiya MF lenses, and some 35mm scans can be downsampled to 2700 dpi. Whatever. There are lots of people who come up with 9MP or so as the digital equivalent of 35. David J. Littleboy [EMAIL PROTECTED] Tokyo, Japan Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
Paul, We may be miscommunicating. The native optical resolution of my Umax PowerLook III is 1200 ppi and for my film scanner around 2780 ppi for 35mm and 1100 for 120 films. If, for the sake of the argument, I want the size of the image to be 1:1 at those resolutions, I would be sending the printer a file whose resolution is more than the printer's native resolution, which means that the printer would be downsampling the file without any extra effort at altering the resolution on my part. Thus my question is it preferable to send the printer images whose unaltered native resolutions are higher than the printer's native resolution of 720/360 ppi or to send the printer images whose unaltered native resolutions are lower than the printer's native resolution of 720/360 ppi. I realize that in practice we would be talking about two different image files and not the same image file with one image file being produced by a scanner with an optical resolution of less than the printer's native resolution and one image file being created by a scanner whose optical resolution is greater than the printer's native resolution wherein both the originals were say 8x10 and were to be printed at the same size. In short, is it theoretically better to downsample than to upsample using the printer, leaving aside questions of if such sampling is better done prior to sending the file to the printer by PS or some other editing application? -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Paul D. DeRocco Sent: Wednesday, October 22, 2003 7:00 PM To: [EMAIL PROTECTED] Subject: [filmscanners] RE: Pixels and Prints From: Laurie Solomon It is very simple Paul; if you scan an image or film frame at 1200 ppi or above and do not down sample in PS or another editing program but send it on to the printer, you will be faced with this choice. It is only if you DO resample downward in this case would you not be faced with the chouce. But if you scan at a particular resolution, and you want the print to be a certain size, then you've already determined whether you have less or more resolution than the printer's native 720ppi resolution. You can of course change the scan resolution, but in most scanners all that does is another software resampling, so whether that's good or bad depends upon the quality of the resampling function. My approach has always been to scan at the native resolution of the scanner, edit and crop to my heart's content, and then, if I suspect aliasing might be a problem, upsample in PS to the next lower submultiple of 720. -- Ciao, Paul D. DeRocco Paulmailto:[EMAIL PROTECTED] Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body --- Incoming mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.528 / Virus Database: 324 - Release Date: 10/16/2003 --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.528 / Virus Database: 324 - Release Date: 10/16/2003 Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
From: LAURIE SOLOMON We may be miscommunicating. The native optical resolution of my Umax PowerLook III is 1200 ppi and for my film scanner around 2780 ppi for 35mm and 1100 for 120 films. If, for the sake of the argument, I want the size of the image to be 1:1 at those resolutions, I would be sending the printer a file whose resolution is more than the printer's native resolution, which means that the printer would be downsampling the file without any extra effort at altering the resolution on my part. Thus my question is it preferable to send the printer images whose unaltered native resolutions are higher than the printer's native resolution of 720/360 ppi or to send the printer images whose unaltered native resolutions are lower than the printer's native resolution of 720/360 ppi. In practice, I think it's a tangled mass of relatively unimportant trade-offs, with no clear answer. Scanning at high resolution reduces the danger of aliasing in the scanner, but increases the danger of aliasing in the printer. The best would be to scan at the highest resolution, and then use software with a good resampling algorithm to resample to the optimum resolution of the printer, or some integer submultiple. -- Ciao, Paul D. DeRocco Paulmailto:[EMAIL PROTECTED] Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
240 dpi is all that is needed. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED] Sent: Monday, October 20, 2003 9:07 PM To: [EMAIL PROTECTED] Subject: [filmscanners] Pixels and Prints I suspect I will 'go digital' sometime in the next year or two. My question regards what type of print output quality I can expect from digital. I print on an Epson 2200 at sizes of up to 13x19 inches. In reality, I tend to leave an inch margin or so around the image, so lets say an image size of 11x17 inches. Conventional teaching with scans (and I suppose that this could be part of the answer..that the conventional holds with scans but not direct digital acquisition) is that for critical sharpness you should be able to send 300ppi to the printer. Say this is overkill and you really only need 250 ppi. By my calculations you would still need 11 megapixels fo an 11x17 image at 250ppi. Yet everyone raves at the output of even the Canon 10D at significantly less resolution. So is the conventional teaching incorrect when it comes to direct digital capture? Perhaps more importantly, how many megapixels are needed for an extremely sharp 11x17 inch print? I realize there are other benefits to digital capture as it translates to printing, such as lack of grain, but sharpness is quite important to me as well. I would appreciate any help in how to look at this as I think about getting a digital body. Right now I am using a 1V and a Polaroid Sprintscan 4000 Plus. A DS1 at 14 or so megapixels and full frame sensor is way too expensive for me...but if a new Canon EOS 3 type digital body were to come out I could see spending up to $2500 or so. Howard Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
Paul, You can get super-sharp prints at 12x18 from a D100 providing the image was super-sharp to start with (I also uprez with QI). I hand-hold my camera most of the time, and buying the 80-200 VR AFS lens has made an enormous difference to my print sharpness. Set the speed to 1/1000 and it is equivalent to 1/8000 and sharp!! (providing the object is not moving too fast of course). I control the speed all the time now, and let the Auto ISO feature take over if I run out of aperture. If you hand-hold at slow/medium speeds, you will not get super-sharp prints unless you are very good with differential USM. Bob Frost. - Original Message - From: Paul D. DeRocco [EMAIL PROTECTED] You're right that you won't get _super_ sharp images from a 6Mp camera at 11x17, but they'll still be quite sharp at 180ppi. I like the results I get with a Canon 10D and an Epson 2200. For some subjects with a lot of sharp lines, you can use tools like the Geniune Fractals plugin to upsize, because it does a good job of artificially preserving edge sharpness. Another alternative in some situations, is to shoot multiple shots and stitch them together. Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
Karl, Yes, but you can get rid of real grain and artifical grain if you use a program like Neat Image. Use it last of all after sharpening and it will get rid of sharpening artefacts as well, or at least reduce them to the level where they are not noticeable. Neat Image Pro+ is my best buy of all time. A 6MP digital image is equivalent to a 2000dpi scan, not a 4000dpi scan which gives 24 MP. My Minolta 5400 gives about 40MP scan (230 MB files!), but some of my D100 images look as good at 12x18. Depends on content. l use Neat Image on both. Bob Frost. - Original Message - From: KARL SCHULMEISTERS [EMAIL PROTECTED] The idea that you won't have grain is somewhat misleading. When you upsize to 11x17, you will have the equiv of grain in the form of digital artifacts. At even 8x10, I can tell the difference between a 35mm film image and a 6mpixel Camera, and it is even more obvious at 11x17. Realistically, a 6mPixel camera is equiv to 4000dpi scan of 35mm film. Which generates some amazing images, but still doesn't quite match film when you enlarge it. Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
Hi Eugene, 240 dpi is all that is needed. Needed? I have images that show more detail (and look better) using up to 480PPI to the printer... Regards, Austin Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
Eugene, 240 dpi is not all that is needed, because the Epson driver upsamples that (or any other dpi you send it) to 720 dpi (desktop printers), using Nearest Neighbour type upsampling. So 720 dpi is what is needed by the driver. The question is can you get better results by upsampling to 720dpi yourself (using QI for example that upsamples with various superior methods - bicubic, lanczos, vector, etc). You seem to be suggesting that you can't, but others suggest you can. Bob Frost. - Original Message - From: Eugene A La Lancette PhD MD [EMAIL PROTECTED] 240 dpi is all that is needed. Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
I've produced very acceptable 13x9s from a 1.68 megapixel camera, the Canon Pro 70. Yes, when you get up close you can see staircasing from the lack of resolution, but in practice you don't examine big pictures close up. And for me the complete absence of film grain makes all the difference. In article [EMAIL PROTECTED], [EMAIL PROTECTED] () wrote: I suspect I will 'go digital' sometime in the next year or two. My question regards what type of print output quality I can expect from digital. I print on an Epson 2200 at sizes of up to 13x19 inches. In reality, I tend to leave an inch margin or so around the image, so lets say an image size of 11x17 inches. Conventional teaching with scans (and I suppose that this could be part of the answer..that the conventional holds with scans but not direct digital acquisition) is that for critical sharpness you should be able to send 300ppi to the printer. Say this is overkill and you really only need 250 ppi. By my calculations you would still need 11 megapixels fo an 11x17 image at 250ppi. Yet everyone raves at the output of even the Canon 10D at significantly less resolution. So is the conventional teaching incorrect when it comes to direct digital capture? Perhaps more importantly, how many megapixels are needed for an extremely sharp 11x17 inch print? I realize there are other benefits to digital capture as it translates to printing, such as lack of grain, but sharpness is quite important to me as well. I would appreciate any help in how to look at this as I think about getting a digital body. Right now I am using a 1V and a Polaroid Sprintscan 4000 Plus. A DS1 at 14 or so megapixels and full frame sensor is way too expensive for me...but if a new Canon EOS 3 type digital body were to come out I could see spending up to $2500 or so. Howard Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
Sorry, there is no hard-and-fast print resolution answer--a lot of it depends on the subject matter. I've gotten 11x17's I was very happy with from my 4MP Olympus E-10. I've also gotten 8x10's that were awful, even though there were no actual problems like focus or noise. One example is people--a tight headshot is very tolerant of low resolution, because the details that drop out are things like individual hairs, things we don't have a huge objection to not seeing. 8x10s from my antique 1.4MP Sony DSC-770 look pretty good. On the opposite end of the spectrum is a group shot with 20 people. Here low resolution means faces with monotooth and missing nostrils and eye-whites--all things that are visually disturbing. 8x10s off my 4MP E-10 look awful, even 8x10s off of 35mm don't look that great, this is still the domain of MF. Comparing digicam pixels to scanner pixels is misleading because scanner pixels are second-generation--4000 scanner pixels=2700 digicam pixels seems empirically like a good approximation, but I don't have research to prove this. And comparing lines resolved between digicams and film is a little misleading anyway--digicam generally have pretty decent MTF right down to their theoretical limit, then fall off to zero. On film, the MTF starts to fall off sooner, but keeps going longer. Assuming 3 pixels/line pair, 300 dpi can resolve a hair under 4 lp/mm. 200 dpi is 2.6 lp/mm. Both well under the standards for a fine enlarger print of 6-8 lp/mm. The catch is that at the 3 lp/mm frequency, the 300 dpi digital probably has better MTF than the enlarger print, even though it loses the ultimate resolution battle. The reason you need 6-8 lp/mm from an enlarger print is not so much that you can actually see that resolution from a normal viewing distance, but that a 10% MTF at 6 lp/mm is a good predictor of a 80%+ MTF at 2-3 lp/mm, which is what really matters. Roger Krueger Eugene A La Lancette PhD MD wrote: 240 dpi is all that is needed. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED] Sent: Monday, October 20, 2003 9:07 PM To: [EMAIL PROTECTED] Subject: [filmscanners] Pixels and Prints I suspect I will 'go digital' sometime in the next year or two. My question regards what type of print output quality I can expect from digital. I print on an Epson 2200 at sizes of up to 13x19 inches. In reality, I tend to leave an inch margin or so around the image, so lets say an image size of 11x17 inches. Conventional teaching with scans (and I suppose that this could be part of the answer..that the conventional holds with scans but not direct digital acquisition) is that for critical sharpness you should be able to send 300ppi to the printer. Say this is overkill and you really only need 250 ppi. By my calculations you would still need 11 megapixels fo an 11x17 image at 250ppi. Yet everyone raves at the output of even the Canon 10D at significantly less resolution. So is the conventional teaching incorrect when it comes to direct digital capture? Perhaps more importantly, how many megapixels are needed for an extremely sharp 11x17 inch print? I realize there are other benefits to digital capture as it translates to printing, such as lack of grain, but sharpness is quite important to me as well. I would appreciate any help in how to look at this as I think about getting a digital body. Right now I am using a 1V and a Polaroid Sprintscan 4000 Plus. A DS1 at 14 or so megapixels and full frame sensor is way too expensive for me...but if a new Canon EOS 3 type digital body were to come out I could see spending up to $2500 or so. Howard Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
on 10/21/03 2:04 AM, Eugene A La Lancette PhD MD at [EMAIL PROTECTED] wrote: 240 dpi is all that is needed. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED] Sent: Monday, October 20, 2003 9:07 PM To: [EMAIL PROTECTED] Subject: [filmscanners] Pixels and Prints I suspect I will 'go digital' sometime in the next year or two. My question regards what type of print output quality I can expect from digital. I print on an Epson 2200 at sizes of up to 13x19 inches. In reality, I tend to leave an inch margin or so around the image, so lets say an image size of 11x17 inches. Conventional teaching with scans (and I suppose that this could be part of the answer..that the conventional holds with scans but not direct digital acquisition) is that for critical sharpness you should be able to send 300ppi to the printer. Say this is overkill and you really only need 250 ppi. By my calculations you would still need 11 megapixels fo an 11x17 image at 250ppi. Yet everyone raves at the output of even the Canon 10D at significantly less resolution. So is the conventional teaching incorrect when it comes to direct digital capture? Perhaps more importantly, how many megapixels are needed for an extremely sharp 11x17 inch print? I realize there are other benefits to digital capture as it translates to printing, such as lack of grain, but sharpness is quite important to me as well. I would appreciate any help in how to look at this as I think about getting a digital body. Right now I am using a 1V and a Polaroid Sprintscan 4000 Plus. A DS1 at 14 or so megapixels and full frame sensor is way too expensive for me...but if a new Canon EOS 3 type digital body were to come out I could see spending up to $2500 or so. Howard Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body -- -- Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body I agree that 240ppi looks pretty darn good. I can get that scanning a 35mm neg with the Minolta Scan Dual II. I've printed 12x18 on 13x19 watercolor paper and it looks pretty fine. Berry Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
Hi Bob, 240 dpi is not all that is needed..., because the Epson driver upsamples that (or any other dpi you send it) to 720 dpi (desktop printers), using Nearest Neighbour type upsampling. So 720 dpi is what is needed by the driver. Just a minor clarification...both of you really mean PPI, as in pixels per inch, which is what you send to the printer...you don't send dots to the printer, the printer, though, in our case, prints dots. Regards, Austin Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
Roger Krueger writes: Comparing digicam pixels to scanner pixels is misleading because scanner pixels are second-generation--4000 scanner pixels=2700 digicam pixels seems empirically like a good approximation, but I don't have research to prove this. My estimate is 4000 scanner pixels=2400 digicam pixels. Here's a scan (the left is an in focus scan and the right an out of focus scan of the same area) first straight, and then carefully downsampled to 2400 dpi. (Velvia 100F) http://www.pbase.com/image/22348855/original http://www.pbase.com/image/22348935/original And comparing lines resolved between digicams and film is a little misleading anyway--digicam generally have pretty decent MTF right down to their theoretical limit, then fall off to zero. On film, the MTF starts to fall off sooner, but keeps going longer. Assuming 3 pixels/line pair, 300 dpi can resolve a hair under 4 lp/mm. 200 dpi is 2.6 lp/mm. Both well under the standards for a fine enlarger print of 6-8 lp/mm. The catch is that at the 3 lp/mm frequency, the 300 dpi digital probably has better MTF than the enlarger print, even though it loses the ultimate resolution battle. The reason you need 6-8 lp/mm from an enlarger print is not so much that you can actually see that resolution from a normal viewing distance, but that a 10% MTF at 6 lp/mm is a good predictor of a 80%+ MTF at 2-3 lp/mm, which is what really matters. Agreed. This is, IMHO, exactly right. David J. Littleboy Tokyo, Japan Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
Roger, Comparing digicam pixels to scanner pixels is misleading because scanner pixels are second-generation--4000 scanner pixels=2700 digicam pixels seems empirically like a good approximation, but I don't have research to prove this. So what if it's second generation? Unless you can analyze the fidelity of it to make claims from, that's simply an argument that has no teeth. Fact is, digicam pixels have some %66 of the red, %66 of the blue and %50 of the green data interpolated. Scanned film data does not. It has all three color values as original information. So, second generation or not, the fidelity (which is what is important) of the data from scanned film far outweighs digicam data of the same resolution. How good the scanned data is, depends a lot on how good the original film image is, as well as how good the scanner/operator is. Not all scanners scan 4000 PPI the same. Even if you recorded Ozzie live with your 8 track tape recorder, my nth generation CD will have a far higher fidelity. Regards, Austin Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
Thats what I get for doing math late at night, my bad. - Original Message - From: Paul D. DeRocco [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Monday, October 20, 2003 10:19 PM Subject: [filmscanners] RE: Pixels and Prints From: KARL SCHULMEISTERS Realistically, a 6mPixel camera is equiv to 4000dpi scan of 35mm film. Which generates some amazing images, but still doesn't quite match film when you enlarge it. 4000dpi comes out to about 4K by 6K, or 24M. A 6Mp camera is closer to a 2700dpi scanner. Save your pennies for when D1s technology makes it down to $2500, or get the 10D as a camera to use when you don't really intend to go much bigger than 8x10 That's only good advice if you're obsessive about sharpness, and intend to examine the prints with a loupe. Believe me, the 10D makes very nice 12x18 prints. -- Ciao, Paul D. DeRocco Paulmailto:[EMAIL PROTECTED] Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
Upsampling always results in some loss - it might be artifacts, it might be loss of tonal gradation. My math was late night error. My practical experience is that I have yet to see a digicam image of less than 10+mPixels that looks as good printed at 11x17 as 35mm scanned at 4000dpi printed to the same level. It might simply be that the regularity of digital artifacting is more noticeable than grain. It just doesn't look that good. And this includes images others have raved about. It may also be a matter of what you look for in an image and how experience/biased the viewing eye is. - Original Message - From: Bob Frost [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Tuesday, October 21, 2003 7:01 AM Subject: [filmscanners] Re: Pixels and Prints Eugene, 240 dpi is not all that is needed, because the Epson driver upsamples that (or any other dpi you send it) to 720 dpi (desktop printers), using Nearest Neighbour type upsampling. So 720 dpi is what is needed by the driver. The question is can you get better results by upsampling to 720dpi yourself (using QI for example that upsamples with various superior methods - bicubic, lanczos, vector, etc). You seem to be suggesting that you can't, but others suggest you can. Bob Frost. - Original Message - From: Eugene A La Lancette PhD MD [EMAIL PROTECTED] 240 dpi is all that is needed. Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
From: [EMAIL PROTECTED] I print on an Epson 2200 at sizes of up to 13x19 inches. In reality, I tend to leave an inch margin or so around the image, so lets say an image size of 11x17 inches. Conventional teaching with scans (and I suppose that this could be part of the answer..that the conventional holds with scans but not direct digital acquisition) is that for critical sharpness you should be able to send 300ppi to the printer. Say this is overkill and you really only need 250 ppi. By my calculations you would still need 11 megapixels fo an 11x17 image at 250ppi. Yet everyone raves at the output of even the Canon 10D at significantly less resolution. So is the conventional teaching incorrect when it comes to direct digital capture? Perhaps more importantly, how many megapixels are needed for an extremely sharp 11x17 inch print? I realize there are other benefits to digital capture as it translates to printing, such as lack of grain, but sharpness is quite important to me as well. You're right that you won't get _super_ sharp images from a 6Mp camera at 11x17, but they'll still be quite sharp at 180ppi. I like the results I get with a Canon 10D and an Epson 2200. For some subjects with a lot of sharp lines, you can use tools like the Geniune Fractals plugin to upsize, because it does a good job of artificially preserving edge sharpness. Another alternative in some situations, is to shoot multiple shots and stitch them together. -- Ciao, Paul D. DeRocco Paulmailto:[EMAIL PROTECTED] Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] Re: Pixels and Prints
The idea that you won't have grain is somewhat misleading. When you upsize to 11x17, you will have the equiv of grain in the form of digital artifacts. At even 8x10, I can tell the difference between a 35mm film image and a 6mpixel Camera, and it is even more obvious at 11x17. Realistically, a 6mPixel camera is equiv to 4000dpi scan of 35mm film. Which generates some amazing images, but still doesn't quite match film when you enlarge it. Sure Genuine Fractals soften out the artifacting you get from the lack of DPI, but they can't make up for lack of tonal content etc. Save your pennies for when D1s technology makes it down to $2500, or get the 10D as a camera to use when you don't really intend to go much bigger than 8x10 - Original Message - From: Paul D. DeRocco [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Monday, October 20, 2003 7:14 PM Subject: [filmscanners] RE: Pixels and Prints From: [EMAIL PROTECTED] I print on an Epson 2200 at sizes of up to 13x19 inches. In reality, I tend to leave an inch margin or so around the image, so lets say an image size of 11x17 inches. Conventional teaching with scans (and I suppose that this could be part of the answer..that the conventional holds with scans but not direct digital acquisition) is that for critical sharpness you should be able to send 300ppi to the printer. Say this is overkill and you really only need 250 ppi. By my calculations you would still need 11 megapixels fo an 11x17 image at 250ppi. Yet everyone raves at the output of even the Canon 10D at significantly less resolution. So is the conventional teaching incorrect when it comes to direct digital capture? Perhaps more importantly, how many megapixels are needed for an extremely sharp 11x17 inch print? I realize there are other benefits to digital capture as it translates to printing, such as lack of grain, but sharpness is quite important to me as well. You're right that you won't get _super_ sharp images from a 6Mp camera at 11x17, but they'll still be quite sharp at 180ppi. I like the results I get with a Canon 10D and an Epson 2200. For some subjects with a lot of sharp lines, you can use tools like the Geniune Fractals plugin to upsize, because it does a good job of artificially preserving edge sharpness. Another alternative in some situations, is to shoot multiple shots and stitch them together. -- Ciao, Paul D. DeRocco Paulmailto:[EMAIL PROTECTED] Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
Karl, Realistically, a 6mPixel camera is equiv to 4000dpi scan of 35mm film. Where on earth do you get that idea? Basicall, your claim is simply not even close. Regards, Austin Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
[filmscanners] RE: Pixels and Prints
From: KARL SCHULMEISTERS Realistically, a 6mPixel camera is equiv to 4000dpi scan of 35mm film. Which generates some amazing images, but still doesn't quite match film when you enlarge it. 4000dpi comes out to about 4K by 6K, or 24M. A 6Mp camera is closer to a 2700dpi scanner. Save your pennies for when D1s technology makes it down to $2500, or get the 10D as a camera to use when you don't really intend to go much bigger than 8x10 That's only good advice if you're obsessive about sharpness, and intend to examine the prints with a loupe. Believe me, the 10D makes very nice 12x18 prints. -- Ciao, Paul D. DeRocco Paulmailto:[EMAIL PROTECTED] Unsubscribe by mail to [EMAIL PROTECTED], with 'unsubscribe filmscanners' or 'unsubscribe filmscanners_digest' (as appropriate) in the message title or body
