Conventional lenses and digital imaging... Oh my!! (was RE: No Pentax digital SLR at PMA)
Brian Walsh wrote: [A comment on a nice summary of definitions and design issues relating to selection of CCD and CMOS arrays for imaging applications, found at http://www.optics-online.com/literature/CCDlens.htm] and Anthony Farr commented: Thanks, Brian, for going the extra yard to get an expert point of view from within the optical industry (rather than yet another I reckon that ... blah, blah, blah). [Snip] I fear that, within two months, someone who [missed all the recurring threads] will enlighten us that all the rumours of digital wide-angle problems are just fear mongering, and that it really makes no difference whether it's film or electronics at the focal plane because the light doesn't know what it's striking! Gawd spare me! Read my lips: film is not the same as an imaging chip, it has some similarities but it also has significant differences. Hi Brian, Anthony, et al., Sheesh, Anthony, you seem a little sensitive about all of this. ;-) The website Brian points out is a nice summary. (By the way, thanks, Brian!) Since I'm apparently one of the folks with a prior I reckon that... blah, blah, blah discourse on imaging optics and sensors, I feel compelled to reply. But don't take it personally -- it's really not meant that way. Would it help lend credence if I started my dreadfully long discourses with I'm a Ph.D. laser spectroscopist with several years experience designing low-light level sensing and imaging systems -- blah, blah, blah instead of Well shucks, I reckon, blah, blah, blah? I find that the former approach usually just pisses people off, and I'm afraid I might end up with The Duchess beating me about the head. I usually just try to let the elegant physics speak for itself. If I fail to convince you, then I just didn't explain it well enough. But I digress One important point Brian's website alludes to is the significance of that microlens/microfilter array. This is really the element that makes a commercially available doped silicon color imaging sensor array (CCD or CMOS) behave much differently than film. This is the element which imposes constraints on the numerical aperture, or field of view, of individual pixels. (Take away this filter/lenslet array, and the differences between silver halide sensor arrays and doped silicon sensor arrays disappear. I'll show you how this is true below) I think we're in complete agreement on the fact that light falloff for film vs. filter/lenslet-equipped color CCDs is different. As well we should be, since it's a consequence of some pretty simple physics. Unfortunately, a lot of folks who happen to find bits of photographic information -- on this list or elsewhere -- may not have sufficient background in optics or electronics. They'll read something like You can't use existing photographic lenses with CCD sensor arrays. They'll then see something erroneous that is passed off as an explanation; that is, CCD sensor arrays are only sensitive to light which strikes perpendicular to the array, and they'll accept that without question. Of course, you and I know that if the rays were all perpendicular to the array, and were thus parallel rays, you would have perfectly collimated light and no image at all. But those without sufficient background in optics will not know this, and they'll erroneously conclude that existing photographic lenses cannot be used with CCD or CMOS sensors. Then someone will offer a correction and say the rays must be nearly parallel. That of course implies that only lenses of rather long focal length can be used with CCD or CMOS arrays. Which of course is utter nonsense. And thus propagates what I've described as the rumors and the fear-mongering. If you'd like to see some real live images collected through short focal length, conventional photographic lenses and sensed by CCD arrays, see the following: http://www.galaxyimages.com/gallery.html http://www.galaxyimages.com/conewidefield.html http://www.galaxyimages.com/orionccd.html The first URL is the gallery. The second was taken with a 19-35mm fl Nikkor camera lens set at 25mmfl at f/4. The third was taken with a 19-35mm fl Nikkor camera lens set at 35mm fl at f/4. Convinced yet? (Some of the others were taken at much longer focal lengths.) Ah, but these were acquired with a monochrome CCD sensor array, you notice. That pesky lenslet/filter thingy is not present in this sensor! OK, so if you want a color sensor array, you have a few design options Option (1): Throw out all of your existing lens designs, and redesign from scratch. However, keep in mind the following constraints from geometric optics; that is, -- Photons travel in straight lines, and no lens design will make them travel through free space to the image plane in curves; -- Light falloff for spherical optics goes as cosine to the fourth power. Option (2): Keep all your time-tested lens designs, and save all the money you'd
Re: No Pentax digital SLR at PMA
Regarding the compatibility of older wide-angle lenses with full-frame CCDs, this on the red herring of CCD illumination from optical supplier Sunix, Inc. at http://www.optics-online.com/literature/CCDlens.htm : The light collection ability of all lenses falls off with increasing field of view. Relative illumination of a lens is defined as the ratio of light intensity at the maximum angle of view to that on-axis. For electronic imager sensors (CCD and CMOS), the off-axis brightness is further reduced by the collection efficiency of imager pixel structure. Many modern imagers use a micro-lens over each pixel to increase the fill-factor. The micro-lens will limit the field of view of the pixel. To be maximally compatible with the micro-lens field of view, the rays emerging from the lens must be within the acceptance angle of the micro-lens for all off-axis rays. This typically require that the primary lens be telecentric in imaging spacing. Non-telecentric lenses can also cause color and resolution cross-talk between adjacent pixels. This will further impair the off-axis performance of the imaging system. Even if sufficient light reaches all of the CCD, the various wavelengths of that light must, of course, be carefully focused. In his survey of Nikon lenses, nature photographer Bjorn Rørslett commented: The presence of colour fringing is in fact typical for most modern designs, since elimination of chromatic aberrations evidently is given fairly low priority. Hopefully, the coming digital era will alter the priorities here since digital cameras do need better chromatic correction than contemporary models. So, if the CCD must receive the various wave lengths of light focused as tightly as possible (something that may have been less of a priority in the decades before digital imaging--read Pentax SMC, M, A, F, FA--than it will become as we are dragged, even if kicking and screaming, into the digital era), we should ask: How close to apochromatic are various Pentax wide-angle lenses? If Pentax invested more effort than other manufacturers in correction of chromatic aberrations, the possibility of a full-frame sensor might be higher than if Pentax gave only average, or below average, priority to that aspect of lens design. Now, what if it isn't just that a given lens must work well with a CCD, but with a _particular_ CCD? Mr. Rørslett reports that a wide angle lens can perform differently even with CCDs of the same size: The 14mm ultra-wide angle lens Nikon designed to give real wide angle performance to a digital camera which includes an effective focal length multiplier (the 2.66 megapixel D1) produces increased color fringing with another CCD of the same 15.6 x 23.7mm size (in the 5.47 megapixel D1X). Oops. The Contax full-frame digital SLR works only with a new series of lenses which were designed specifically for the new range of (autofocus) cameras, which included the planned digital model from inception. The counting teeth scenario isn't relevant here: The question is whether existing Pentax wide-angle lenses will work with a full-frame CCD, not if lenses of a new design will work with a new Contax model. Perhaps the use of older wide angle lenses on a future full-frame sensor Nikon model will give us a hint, even if Pentax won't open up and say Aaaah. - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
Re: No Pentax digital SLR at PMA
Thanks, Brian, for going the extra yard to get an expert point of view from within the optical industry (rather than yet another I reckon that ... blah, blah, blah). But somehow I fear that, within two months, someone who missed this thread, or the previous thread on the subject, or the one before that, will enlighten us that all the rumours of digital wide-angle problems are just fear mongering, and that it really makes no difference whether it's film or electronics at the focal plane because the light doesn't know what it's striking! Gawd spare me! Read my lips: film is not the same as an imaging chip, it has some similarities but it also has significant differences. Regards, Anthony Farr - Original Message - From: Brian Walsh [EMAIL PROTECTED] Regarding the compatibility of older wide-angle lenses with full-frame CCDs, this on the red herring of CCD illumination from optical supplier Sunix, Inc. at http://www.optics-online.com/literature/CCDlens.htm : (snip) - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
Re: No Pentax digital SLR at PMA
Mark Roberts [EMAIL PROTECTED] wrote: This red herring has been trotted out a lot. It's bogus. in reponse to Brian Walsh [EMAIL PROTECTED] who wrote: The issue raised explains it: CCD's apparently cope poorly with rays which strike them at many angles which are fully compatible with film. Using a smaller than full-frame CCD with conventional lenses avoids those paths nearer the edges of the image circle which strike the recording surface at more extreme angles. Well, Mark, the problem with your assertion is that their are no full frame digital 35mm cameras to test your claim (unless the C***n Eos1D is already circulating - I don't know its release status or specs). The Cx hasn't hit the shops yet but I believe it's using a CMOS chip, a type which apparently are more receptive to oblique rays than are CCDs. What is available are some Kodak models built on N***n and C***n chassis that are almost full frame, and I've read first person reports confirming that WA fall-off is indeed a problem with them. You could be assuming (excuse me if you're not) that because 24mm x 36mm and larger chips are in service on medium format and bigger cameras then the doubts about WA use are dispelled. Problem with that conclusion is that those cameras have a hugely increased back-focus compared to 35mm cameras and AFAIK their imaging chips are all less than full format in their applications, so there's no way any parallel can be drawn. Regards, Anthony Farr - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
Re: No Pentax digital SLR at PMA
Anthony Farr wrote: You could be assuming (excuse me if you're not) that because 24mm x 36mm and larger chips are in service on medium format and bigger cameras then the doubts about WA use are dispelled. No, I'm assuming it won't be a problem because the difference in angle of incidence is only about 5 degrees. Here's a really informative Bill Peifer post on the subject I dug out of the archives: I'm curious where this whole idea of CCD sensors requiring (or preferring) perpendicular rays originated. I'm pretty convinced that it must have originated because somewhere along the line, something got taken out of context, and a fundamentally incorrect idea grew from there. From the standpoint of the underlying physics, Tom is absolutely right -- the purpose of a lens is to bring an image to critical focus at the focal plane, and the nature of the sensor (film, CCD, CMOS, or other) isn't particularly relevant. After all, if all the light rays strike the sensor perpendicularly, then they are necessarily parallel and thus cannot form an image at the focal plane! I suspect that this perpendicular-ray story -- dare I say legend? -- may have originated from a misinterpretation of the characteristic behavior of CCD sensors. We all know that in single-chip color CCD sensors, some of the pixels are sensitive to red, others to green, and still others to blue. For the case of color cameras with single CCD sensors, color sensitivity is imparted to a particular pixel by incorporating a microscopic optic -- a lenslet and filter -- in front of that pixel, which I believe is accomplished as part of the manufacturing process for the sensor chip. I can imagine that the numerical aperture of this microscopic optic may not be terribly large, and it might very well constrain the field of view of its corresponding pixel. Maybe someone that knows more about chip fab can comment on this. Anyway, although each individual pixel may very well be looking through an optic with small numerical aperture, it's only looking a very short distance (microns? tenths of microns?) to the illuminated spot on the focal plane directly in front of it. In fact, this is precisely what you want. If each pixel had a more wide-angle view, it would not only register the intensity of light directly in front of it, but it would also register the intensity of light from a immediately adjacent pixels (perhaps pixels intended to sense a different color), resulting in a spatially and chromatically degraded image. The characteristics of the macroscopic, analog lens mounted onto the front of the camera -- focal length, f-number, etc. -- isn't particularly relevant, except that a faster analog lens will make each pixel-size spot of light at the focal plane correspondingly brighter. Bill Peifer Rochester, NY -- Mark Roberts www.robertstech.com - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
RE: No Pentax digital SLR at PMA
Mark wrote: Nope, that wasn't anything to do with the redesign of the lenses. Are you quite certain that the Carl Zeiss lens designers feel (as Olympus lens designers apparently do not) that CCD imaging characteristics need not be considered in the design of lenses meant to be used with a CCD? Which is exactly why, even if your unsubstantiated hypothesis were true, they wouldn't need to redesign all the lenses for a CCD: They'd just have to come up with wide angles of a more retrofocus design. Exactly, Mark. That's why I suggested that new lenses could be designed to cope with the specific requirements of digital imaging. I raised the (limited) analogy of the generational change of wide angle lenses to accommodate the mirror boxes in SLRs by means of retrofocus designs, and suggested that some older designs, without analogous changes, would not be very useable on a digital camera with a full-frame CCD. I reread my posts, and--although I really meant to confine my comments to wide angle lenses--I certainly blew it when I tried to edit my first post a bit before I submitted it. I didn't mean to suggest that it would be necessary to, as you say, redesign all the lenses for a CCD, and I explicitly stated in my second post that such redesign might be unnecessary with lenses with more nearly parallel light rays, but could be crucial to the successful use of wide angle lenses with a full-frame CCD camera. I believe I indicated, and you disagreed, that: (1) full-frame CCDs such as the Phillips CCD in the defunct Pentax digital prototype could have problems with some (wide angle) lenses; (2) since Contax designed a brand new lens line to work with the N series cameras (which, from the outset, included plans for a full-frame digital model), it's likely that Carl Zeiss engineers had the wit to consider the specific characteristics of the Phillips CCD when designing the new lenses; and that (3) the Pentax digital model might not have fared as well with existing (wide angle) Pentax lenses which--quite unlike the new N-mount Carl Zeiss lenses for the Contax-- were of necessity designed without consideration for the particular imaging qualities of the full-frame Phillips CCD; and (4) it's possible that Pentax considered possible deficits in the performance of existing Pentax wide-angle lenses in the process which lead to the decision to cancel production of the Pentax full-frame CCD model which debuted last year. Olympus, which markets cameras with a designed for digital theme, may be no more believable than the Pentax marketing sources which you quoted, and which I suggested might be telling only part of the story of the cancellation of the MZ-digital. Nonetheless, Olympus very clearly indicates that light striking the CCD at acute angle angles will produce increased blooming and loss of detail. If this is, as you suggest, a red herring, I'd be delighted to learn why. - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
RE: No Pentax digital SLR at PMA
Alexander Krohe wrote: I may be wrong here, but I don't think for any wide retrofocus angle lens, the light rays will hit the film plane at an acute angle. Not even *close* to an acute angle. Here's a cute (pun intended) story: When I was a a kid and my mother was working on her PhD in Medieval Literature she told me this great story: One day some medieval philosophers were having an argument. The subject was the number of teeth in a horse's mouth. One maintained that it couldn't be a multiple of 12 because that was the number of Jesus' apostles. Another claimed it couldn't be a multiple of 6 because god created the world in 6 days. A third claimed it *ought* to be a multiple of one of these numbers, for precisely the reasons mentioned! A loud debate ensued until one of their students, clearly too young and ignorant to appreciate the finer points of the dialectic, did something which totally shocked them all. He went outside, found a horse and counted its teeth. In that great spirit, I decided to conduct my own tooth counting exercise. The newest hot digital SLR is the Canon EOS-1D. Although it has the disadvantage of one of the largest CCDs currently evailable, it is clearly a high end product intended to satisfy the most discriminating photographers. Its CCD image area is 27.0mm x 17.8mm, which gives an image circle of 32.3mm. The film-plane-to-lens-flange distance for Canon EOS lenses is 44mm. Simple trigonometry reveals that the angle subtended by a line from the edge of the image circle to the center of the lens axis at the flange is 69.7 degrees. The image circle for full-frame 35mm is 43.3mm. Although this will make the angle a little farther from 90 degrees, this is slightly offset in the case of Pentax by a film-plane-to-lens-flange distance of 45.5mm. The net result is an angle of 64.6 degrees at the edge of the image circle. Clearly not as good as the Canon, but the difference of 5.1 degrees is far from earthshaking. Incidentally, carrying out these calculations for the made for digital Contax N1 yields an angle of 67.4 degrees. *Ever* so slightly better (by 2.8 degrees) than the Pentax, but 2.4 degrees *worse* than the designed for film Canon lens mount (at least with the CCD in the EOS-1D). To sum: Canon EOS-1D angle = 69.7 degrees Contax N1-D angle = 67.4 degrees Pentax full-frame = 64.6 degrees The largest difference between these three is an insignificant 5.1 degrees and the hypothetical Pentax full-frame camera would only be 2.8 degrees worse than the made for digital Contax. -- Mark Roberts www.robertstech.com - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
RE: No Pentax digital SLR at PMA
Mark wrote: . . . I decided to conduct my own tooth counting exercise. That's a cute story, and you can be commended for actually calculating the angles at which light projected from a point at the axis of the lens at the lens flange would strike the edge of a CCD, but your tooth counting would be more meaningful in the context of this discussion if wide angle lenses for each of the lens mounts actually projected light precisely from the plane of the lens flange. - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
Re: No Pentax digital SLR at PMA
Brian Walsh [EMAIL PROTECTED] wrote: Mark wrote: . . . I decided to conduct my own tooth counting exercise. That's a cute story, and you can be commended for actually calculating the angles at which light projected from a point at the axis of the lens at the lens flange would strike the edge of a CCD, but your tooth counting would be more meaningful in the context of this discussion if wide angle lenses for each of the lens mounts actually projected light precisely from the plane of the lens flange. Yeah, but due to the mirror it's close. Or at least the distance can't be much less (if the distance were greater it wouldn't matter). I calculated for several different film-plane-to-lens-flange distances and the angle doesn't vary much until you get far out of the range of any existing SLR lens mount. And actually, it wasn't fair to call my exercise a counting of teeth in the sense of the original story. That'll come when there are actual examples of Contax N1 cameras being tested. -- Mark Roberts www.robertstech.com - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
Re: No Pentax digital SLR at PMA? (WAS: Cool colors: blue, purple...)
On Thu, 31 Jan 2002 10:53:03 +0100 Pål Audun Jensen [EMAIL PROTECTED] wrote: However, there are anonymous posting an Japanese Pentax forums that Pentax will release a 3Mpix digital slr built around the MZ-S chassis. According to this rumor it will be released in March and cost 1200USD (presumably in Japan). Only time will tell if this information is credible or not... Whats the point of releasing a 3Mp SLR, when 6 is the accepted norm and now striving for 8-12? Well, I suppose you have to start somewhere... kevin - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
Re: No Pentax digital SLR at PMA=3 F (WAS: Cool colors: blue, purple...)
Kevin Waterson wrote: Pål wrote: However, there are anonymous posting an Japanese Pentax forums that Pentax will release a 3Mpix digital slr built around the MZ-S chassis. According to this rumor it will be released in March and cost 1200USD (presumably in Japan). Only time will tell if this information is credible or not... Whats the point of releasing a 3Mp SLR, when 6 is the accepted norm and now striving for 8-12? After the fiasco of the original MZ-Digital, Pentax realize they need to get something - ANYTHING - into the digital SLR market quickly to assure the public thet Pentax is going to remain a vialble system. If they don't people will start bailing out of the Pentax system in droves. I said last year that I thought 2002 would be pivotal and I'm even more convinced of that now. Olympus has killed off its OM line because it's incompatible with the lens system of their upcoming digital SLR. Contax looks set to get their N1-D on the market, even if it is late. Only Minolta and Pentax left out now and I'm sure both have cameras under development. Pentax is at a disadvantage because of running down a blind alley so long with the original MZ-Digital. Perhaps they had a less expensive digital SLR on the drawing boards all along but if not they've only been working on it since the MZ-Digital was cancelled in December. If that's the case it's *way* too early to expect anything at PMA. -- Mark Roberts www.robertstech.com - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
RE: No Pentax digital SLR at PMA=3 F (WAS: Cool colors: blue, purple...)
It was shelved in mid-october publicly. Which means they probably started on a backup a month or so before that, at least. Could well be ready for PMA. Perhaps the lack of formal announcment is because the camera is hardly ground breaking in the industry, and they are a bit embarrassed. If they dont show anything, that would be even worse because everyone would be saying 'where is the digital you had last year - now you have nothing!' -Original Message- From: Mark Roberts [mailto:[EMAIL PROTECTED]] Sent: 31 January 2002 13:29 To: [EMAIL PROTECTED] Subject: Re: No Pentax digital SLR at PMA=3 F (WAS: Cool colors: blue, purple...) Kevin Waterson wrote: Pål wrote: However, there are anonymous posting an Japanese Pentax forums that Pentax will release a 3Mpix digital slr built around the MZ-S chassis. According to this rumor it will be released in March and cost 1200USD (presumably in Japan). Only time will tell if this information is credible or not... Whats the point of releasing a 3Mp SLR, when 6 is the accepted norm and now striving for 8-12? After the fiasco of the original MZ-Digital, Pentax realize they need to get something - ANYTHING - into the digital SLR market quickly to assure the public thet Pentax is going to remain a vialble system. If they don't people will start bailing out of the Pentax system in droves. I said last year that I thought 2002 would be pivotal and I'm even more convinced of that now. Olympus has killed off its OM line because it's incompatible with the lens system of their upcoming digital SLR. Contax looks set to get their N1-D on the market, even if it is late. Only Minolta and Pentax left out now and I'm sure both have cameras under development. Pentax is at a disadvantage because of running down a blind alley so long with the original MZ-Digital. Perhaps they had a less expensive digital SLR on the drawing boards all along but if not they've only been working on it since the MZ-Digital was cancelled in December. If that's the case it's *way* too early to expect anything at PMA. -- Mark Roberts www.robertstech.com - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org . - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
RE: No Pentax digital SLR at PMA
If they dont show anything, that would be even worse because everyone would be saying 'where is the digital you had last year - now you have nothing!' It may be embarassing, but that's what's gonna happen. I hope they have *something* exciting to show at PMA to celebrate the 50th birthday of the Asahiflex, but it isn't going to be a digital SLR. They just haven't had time, even if development began before the MZ-Digital got cancelled. -- Mark Roberts www.robertstech.com - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
RE: No Pentax digital SLR at PMA=3 F (WAS: Cool colors: blue, purple...)
It may well be not too early to expect anything... Like Rob was saying they may have been working on it since way before December. But also dont discount the fact that they wouldn't be designing the camera from scratch. It seems likely that it would be a conversion of the MZ-D design to use an alternative CCD at a lower resolution. Most of the design being the same or very similar to the MZ-D. This is pure speculation, but it seems to me that it could serve several purposes, such as getting back into the digital SLR market at the same time as recouping development costs from the MZ-D project. We shouldn't forget that it seems the MZ-S was designed to be used as the basis for a digital too, so the design challenges of creating digital SLR's from this chassis should be greatly reduced. Regards, /\/\ick... - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
RE: No Pentax digital SLR at PMA=3 F (WAS: Cool colors: blue, purple...)
On Thu, 31 Jan 2002, Rob Brigham wrote: because everyone would be saying 'where is the digital you had last year - now you have nothing!' Am I the only person who'd be happy with a low end digital SLR that at least TOOK my K mount lenses? I'm not planning on using digital for anything or even everything, but digital sure is convienent. And fun. I still break out my Casio QV-10a, with its gigantic 320x240 pixel pictures, and I enjoy it immensely. I'd LOVE to have a CHEAP digital body that accepted my lenses. It wouldn't have to be anything special, just to knock around with, like all the other digital PS cameras out tehre. I can't imagine I'm the only one with these ideas, as well. -- http://www.infotainment.org The destructive character is cheerful. - Walter Benjamin - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
RE: No Pentax digital SLR at PMA? (WAS: Cool colors: blue, purple...),
Mick wrote: It may well be not too early to expect anything... Like Rob was saying they may have been working on it since way before December. But also dont discount the fact that they wouldn't be designing the camera from scratch. It seems likely that it would be a conversion of the MZ-D design to use an alternative CCD at a lower resolution. Most of the design being the same or very similar to the MZ-D. This is in line with what Pentax stated in the MZ-D cancel press release. Here it's contents is freely translated from swedish: Pentax have decided to cancel further development of the [MZ-D shown at Photokina] and will instead concentrate on developing a new and competitive digital slr. Based on the experience and knowledge from developing the prototype [MZ-D], a new series of competitive models (thats right; modelS) that comply to market demands are now being developed. Pål - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
Re: No Pentax digital SLR at PMA? (WAS: Cool colors: blue, purple...)
Yeah. :( Let's just bitch about them getting something out the door for right now...we can gripe about its shortcomings after it clears that first hurdle. Dan Scott [EMAIL PROTECTED] Whats the point of releasing a 3Mp SLR, when 6 is the accepted norm and now striving for 8-12? Well, I suppose you have to start somewhere... kevin - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
Re: No Pentax digital SLR at PMA? (WAS: Cool colors: blue, purple...)
Whats the point of releasing a 3Mp SLR, when 6 is the accepted norm and now striving for 8-12? Well, I suppose you have to start somewhere... kevin 2 mp digicams outsell 3 mps, and 3 mps outsell 4 mps. And actually, it's the implementation that matters. The more pixels, the higher the incidence of hot or stuck pixels and noise. Furthermore, the larger the file sizes, the longer it takes to download into the buffer and the fewer shots the buffer can hold and the fewer shots fit on any given size SM or CF card and so forth More pixels doesn't always mean better. The 3 mp Canon D30 beats the crap out of the 5 mp Nikon Coolpix 5000 for image quality. (Of course, the D60 is coming) Number of pixels is an easy-to-understand measure for most consumers, like horsepower or top speed. Americans love excess, no matter what it is, and no matter how contrary to good sense it might be (I mean, why are Extra Strength pain relievers appealing, when you can just take two of the normal strength ones and get more medicine than is in one Extra Strength tablet? It makes no sense. Why is a car with a 165 top speed better than one with a 155 to speed if you'll never drive over 100?). And while it would be foolish for me to say X number of megapixels is enough--nobody can know where it's all going to shake out--it's at least true that an infinitely increasing number of pixels isn't infinitely desirable. And so far, the 5 mp cameras haven't exactly set the world on fire for image quality. In many cases they're no better than the 4 mp cameras and in some cases they're WORSE. Assuming these rumors about the MZ-Dn g are true at all, Pentax is FAR smarter to release a 3 mp camera for $1200 than a 6 mp camera for $7000. It's all about balance --Mike - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
RE: No Pentax digital SLR at PMA=3 F (WAS: Cool colors: blue, purple...)
--- gfen [EMAIL PROTECTED] wrote: On Thu, 31 Jan 2002, Rob Brigham wrote: because everyone would be saying 'where is the digital you had last year - now you have nothing!' Am I the only person who'd be happy with a low end digital SLR that at least TOOK my K mount lenses? NO! I would also love to have a camera like this. Like I've said in an earlier post, three MP is more than enough for the editorial and spot news stuff that I do (don't think I've ever run a photo more than about 5x7in). For sports I'll still have my good ole pz1p. As long as it takes all my lenses and my flashes I will be a happy camper. Actually if it is truly going to only be about $1,200us I will be an ~extremely~ happy camper. Nick Great stuff seeking new owners in Yahoo! Auctions! http://auctions.yahoo.com - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
RE: No Pentax digital SLR at PMA
Mike Johnston wrote: More pixels doesn't always mean better. The 3 mp Canon D30 beats the crap out of the 5 mp Nikon Coolpix 5000 for image quality. The D30 is actually quite a camera. I'd be quite happy if Pentax produced a camera as good as the D30--and if I could afford it. One sticking point for many photographers seems to be that the image sensor on most digital cameras is smaller than two frames of old movie stock. The full-frame CCD on the new Contax requires a whole new line of lenses; the redesign undoubtedly included more than adding autofocus, so the new lenses--unlike the excellent older lenses--would provide light paths that would work with the large CCD. I really doubt that our existing Pentax lenses will ever be useful on a full frame Pentax digital camera. - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
Re: No Pentax digital SLR at PMA? (WAS: Cool colors: blue, purple...)
On Thursday, January 31, 2002, at 04:18 AM, Kevin Waterson wrote: Whats the point of releasing a 3Mp SLR, when 6 is the accepted norm and now striving for 8-12? I would imagine in order to offer a low-cost entry level digital SLR that mated with their existing lenses. The quoted $1200 potential street price seems quite low, but I haven't been pricing digital SLRs lately. What does something like a D30 go for? -Aaron - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
RE: No Pentax digital SLR at PMA
-- Original Message -- The full-frame CCD on the new Contax requires a whole new line of lenses; Nope. Uses the same lenses as the film N1. the redesign undoubtedly included more than adding autofocus, The autofocus redesign was needed to insure the regidity of the focusing mechanism in order to maintain proper alignment between the lens and the film plane. Or so Contax claimed. They were always very picky about this factor, though: They're the ones who made a camera (the RTS III) with a vacuum film pressure plate. so the new lenses--unlike the excellent older lenses--would provide light paths that would work with the large CCD. ?? Contax is able to use the same lenses with the digital and film versions of their SLR. The light path is the same: The light goes from the back of the lens to the front of the film/CCD. I really doubt that our existing Pentax lenses will ever be useful on a full frame Pentax digital camera. This has already been done with the MZ-Digital in prototype form. The issues were heat generation/dissipation, competetive pricing in a rapidly changing marketplace and availability of the Philips CCD. -- Mark Roberts www.robertstech.com - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
RE: No Pentax digital SLR at PMA
... I really doubt that our existing Pentax lenses will ever be useful on a full frame Pentax digital camera. Why? What would prevent these lenses from being used on a full frame digital camera? Alexander Great stuff seeking new owners in Yahoo! Auctions! http://auctions.yahoo.com - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
Re: No Pentax digital SLR at PMA
... I really doubt that our existing Pentax lenses will ever be useful on a full frame Pentax digital camera. Why? What would prevent these lenses from being used on a full frame digital camera? Yes indeed, ~please~ tell us why. (Inquiring minds want to know.) ~I~ certainly hope that your pessimistic statement is wrong - ~I~ (and many others here on the PDML) have a sizeable investment in Pentax glass that I/we have been expecting to be able to eventually put to use on a full-frame 35mm format dSLR. Fred - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
Re: No Pentax digital SLR at PMA=3 F (WAS: Cool colors: blue, purple...)
Same here Bob, I spent about the same on a Fuji 6900, which is again a 3MP camera. I'd love to have a decent, sub-$1000 digital SLR body, CCD or CMOS, doesn't really matter. Canon showed it can be done with CMOS and done well. Hopefully, Pentax may get the idea...:) John - Original Message - From: [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Thursday, January 31, 2002 4:37 PM Subject: RE: No Pentax digital SLR at PMA=3 F (WAS: Cool colors: blue, purple...) gfen wrote: I'd LOVE to have a CHEAP digital body that accepted my lenses. It wouldn't have to be anything special, just to knock around with, like all the other digital PS cameras out there. I can't imagine I'm the only one with these ideas, as well. ME TOO. Just laid out $700 for a Sony 3.1 Mpixel. Why can't I use my Pentax lenses? Bob S. - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org . - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
Re: No Pentax digital SLR at PMA
Brian Walsh [EMAIL PROTECTED] wrote: Pulling on my high rubber boots, and replying to some replies to my earlier reply (I'm in digest mode): Nope. Uses the same lenses as the film N1. Yes, those are the lenses I meant. I believe they were designed to allow a nearer-to-90 degree angle of the light path to the sensor (or film, depending on which new N model to which the new lenses are mounted) than is required for (wide angle) lenses designed only for use with film, such the older (though excellent) Carl Zeiss lenses for Contax. Nope, that wasn't anything to do with the redesign of the lenses. Even if they moved the lens-flange-to-film-plane distance out a full centimeter it would have *very* little effect on the angle at which the light rays strike the film. Why? What would prevent these lenses from being used on a full frame digital camera? The issue raised explains it: CCD's apparently cope poorly with rays which strike them at many angles which are fully compatible with film. Using a smaller than full-frame CCD with conventional lenses avoids those paths nearer the edges of the image circle which strike the recording surface at more extreme angles. This red herring has been trotted out a lot. It's bogus. In some ways this situation is analogous to the required redesign of more-or-less symmetric wide angle lenses to clear the mirror box on the new SLRs. Which is exactly why, even if your unsubstantiated hypothesis were true, they wouldn't need to redesign all the lenses for a CCD: They'd just have to come up with wide angles of a more retrofocus design. Some of you may be interested in a white paper from Schneider, which discusses the differences between lenses for digital and film cameras: http://www.schneideroptics.com/info/white_papers/optics_for_digital_photography.pdf Fascinating paper...which doesn't make ANY mention of the mythical wide angle lenses won't work because of the angle of the light reaching the CCD problem. And there's a good reason they don't mention it... -- Mark Roberts www.robertstech.com - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
