filmscanners: Re: filmscanners: New auto adjust software on it's way
Preston wrote: (I remember an article in Scientific American 15 to 20 years ago about the improvement of photographic images (I think they were alluding to spy satellite images) to eliminate/reduce blur due to camera motion and lens focus (or lack thereof). That article may have been concerned with something I learned about at university - inverse fourier transforms. If you can map the aberrations in a satellite lens system while it is still on earth and make a transform from it, you can actually use an inverse transform to remove the aberrations. The result is a sharper image than the camera actually saw. I know this technology has been used with military spy satellite images, but I don't know where else it may have been used. It would be difficult to use on a commercial basis due to the need to map the aberrations of the lens system. It would be wonderful if it could be used in a scanner, because theoretically it ought to be possible to remove aliasing and lens aberrations from the scanner optics. (but I've discussed it before and I won't bore everyone with it again! :) Rob Rob Geraghty [EMAIL PROTECTED] http://wordweb.com
Re: filmscanners: New auto adjust software on it's way
Steve Greenbank wrote: I never claimed their examples had any aesthetic quality, but I do think the software appears to be pretty impressive. Save image 25 or 26 and see if you can get anywhere near the processed example they show you. Steve I took a look at this web site and I do find the software most interesting. I find they over-do the edge sharpening, but the smoke and haze images were pretty amazing. Since this is a NASA technology is it going to be public domain? Art
Re: filmscanners: Re: filmscanners: New auto adjust software on it's way
Rob writes: If you can map the aberrations in a satellite lens system while it is still on earth and make a transform from it, you can actually use an inverse transform to remove the aberrations. The result is a sharper image than the camera actually saw. No, it is just a _different_ image. You cannot create information that was not captured by the camera in the first place, but you can rearrange it so that it looks more useful to a human being. If you know the exact way in which light rays will be misdirected in a lens, you can redirect them through computer processing to arrive at an image that shows approximately what a perfect lens would have produced. However, if any aberrations or other defects caused a loss of information in the captured image, there is nothing you can do to restore that information. An area that is simply outside the plane of focus, for example, cannot be put into sharp focus by post processing. It would be difficult to use on a commercial basis due to the need to map the aberrations of the lens system. It would be cheaper just to design and build a better lens. The military uses this method because they are already using the best lenses that can be made, and so the only way to do better is with a technique that is even more expensive than designing good lenses. But for ordinary photographic lenses, which generally do not push the limits of what is possible, it would be cheaper to just make the lens better than to spend money on extremely costly analysis and post-processing.
Re: filmscanners: Re: filmscanners: New auto adjust software on it's way
That article may have been concerned with something I learned about at university - inverse fourier transforms. Right. It did involve fourier transforms of some sort (I used to have some idea of what that means) but applied to the image not the lens, if I am remembering right. John M.
Re: filmscanners: Re: filmscanners: New auto adjust software on it's way
There are a few software packages designed to do just this for astronomical images.. Lucy-Richardson Deconvolution, Maximum Entropy plus a couple more algorithms.. very cpu intensive (forget about using a Pentium 200). I have not been impressed by the results, too much work for an incremental improvement in image quality.. at the end I just think that its better to use a good lens, properly focused, in the first place.. it does have a place in removing environmental blurring effects. These algorithms were designed to improve the images coming from the Hubble Space Telescope, before the optics were repaired in orbit. Here is a page with before and after results: http://www.image-scientist.com/deconvolve.htm Perhaps I can see something like this added to scanning software.. but note that the algorithm has to be finely tuned to the hardware. Rob Geraghty [EMAIL PROTECTED] wrote: That article may have been concerned with something I learned about at university - inverse fourier transforms. If you can map the aberrations in a satellite lens system while it is still on earth and make a transform from it, you can actually use an inverse transform to remove the aberrations. The result is a sharper image than the camera actually saw. I know this technology has been used with military spy satellite images, but I don't know where else it may have been used. It would be difficult to use on a commercial basis due to the need to map the aberrations of the lens system. It would be wonderful if it could be used in a scanner, because theoretically it ought to be possible to remove aliasing and lens aberrations from the scanner optics. (but I've discussed it before and I won't bore everyone with it again! :) Rob Herm Astropics http://home.att.net/~hermperez
Re: filmscanners: New auto adjust software on it's way
(I remember an article in Scientific American 15 to 20 years ago about the improvement of photographic images (I think they were alluding to spy satellite images) to eliminate/reduce blur due to camera motion and lens focus (or lack thereof). I've been meaning to go to the library to look the article up to see if the results were as impressive as I remember them.) Preston Yeah, that article has stuck in my mind also. I remember that the method had to do with mathematically analyzing circles of confusion to sharpen unsharp images (don't remember anything about motion blur, but it might have been there). I onced asked about it on some list or other and someone mentioned that there was some problem or other. Be curious if anyone has any less vague info about the technique. John M.
RE: filmscanners: New auto adjust software on it's way
Yeah, that article has stuck in my mind also. I remember that the method had to do with mathematically analyzing circles of confusion to sharpen unsharp images (don't remember anything about motion blur, but it might have been there). I onced asked about it on some list or other and someone mentioned that there was some problem or other. Be curious if anyone has any less vague info about the technique. John M. WARNING: science and math explanation - please skip if not interested A simple way of looking at the image formed by an optical system to consider the image to be the convolution between the ideal image and the point spread function for the optics. The ideal image is just the image that you would have if the optics had no aberrations and light did not diffract. The point spread function is the real image that would form if you were looking at a point source, such as a star. The convolution is a two dimensional integration that combines the point spread function with each point in the ideal image. If the ideal image consists of just one star, the real image would be a single point spread function properly located and with the correct intensity. Add another star to the ideal image and add the corresponding point spread function to the real image. Keep adding points to the ideal image until it looks like the scene you are photographing and add the corresponding point spread function to the real image. If the array of points looks sufficiently close the input scene the real image (smeared by the point spread function) will be what finally reaches the film. Various complications arise. To model an image of a colored object the above process needs to be repeated for the different colors. If the point spread function varies across the image (as it would for any real optics) then the appropriate point spread function must be used. Instead of convolving the ideal image with the point spread function, the mathematically equivalent operation can be carried out using Fourier transforms. Instead of doing a two dimensional integration one Fourier transforms both the ideal image and the point spread function, multiplies them together, and then performs an inverse Fourier Transforms. The end result is the same smeared image the convolution obtained. Long ago it was realized that doing the math using Fourier transforms was both quicker and it would allow the smearing to be undone, at least in principle. If the smeared image is just the product of the point spread function and the ideal image, then the ideal image should be the smeared imaged divided by the point spread function. There are MAJOR problems with this simple minded approach, but it is the basis of most current imagine sharpening techniques. Some of the problems include dividing by zero, noisy images, and inadequate modeling of the point spread function. Various methods have been proposed to overcome the problems, but only a small class of images are practical to sharpen. Stellar images from the Huble telescope sharpen very nicely. Images of grandma taken with a cheap zoom lens are a lost cause.
RE: filmscanners: New auto adjust software on it's way
I have to say this is a complete load of baloney. With one Levels setting, e.g.: input black 0 input gamma 2.5 input white 255 output black 0 output white 180 followed by USM: Amount 200 Radius 200 followed by USM: Amount 100 Radius 1 I can get something just like image 8 Retinexed, for example. It definitely isn't rocket science we're seeing here. I guess Joe Bloggs will love it though. Jawed
RE: filmscanners: New auto adjust software on it's way
Call me Bloggs. I'll take it Ian At 01:42 31/08/01 +0100, you wrote: I have to say this is a complete load of baloney. With one Levels setting, snip I can get something just like image 8 Retinexed, for example. It definitely isn't rocket science we're seeing here. I guess Joe Bloggs will love it though. Jawed
Re: filmscanners: New auto adjust software on it's way
John writes: I remember that the method had to do with mathematically analyzing circles of confusion to sharpen unsharp images (don't remember anything about motion blur, but it might have been there). This would work for satellite photos, in which the distance to the subject is known and virtually constant throughout the field; it would not work for ordinary photos, because the scene being photographed contains elements at all different distances, and without knowledge of the distance of each element in the image, it would not be possible to undo the effects of aberration (aberration varies with distance from the focus point of the lens, as do the circles of confusion, and it would smear the data enough to make recovery of a sharp image impossible). However, if you know that everything in the image is exactly 25 miles away (at infinity, in other words), you can work backwards a lot more easily. For ordinary photography, it would still be easier to just build a sharper lens. And there are lots of things that you just would not be able to undo with post-processing, anyway.
Re: filmscanners: New auto adjust software on it's way
I never claimed their examples had any aesthetic quality, but I do think the software appears to be pretty impressive. Save image 25 or 26 and see if you can get anywhere near the processed example they show you. Steve - Original Message - From: Winsor Crosby [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Tuesday, August 28, 2001 8:23 PM Subject: Re: filmscanners: New auto adjust software on it's way From: http://www.steves-digicams.com/diginews.html The software automatically enhances digital images. Samples of what it can do here: http://dragon.larc.nasa.gov/retinex/pao/news/ 8,10,25,26 are little short of amazing. Some of the others are less impressive (22 in particular looks wrong) hopefully there are still some user controls. This is presumably the software they used to spy on us from sattelites and hence is a pure digital system so it probably does nothing for dust, scratches and grain :-( Steve P.S. It's probably a bit slow on Pentium Pro 200's That is one bunch of ugly photos, before and after. -- Winsor Crosby Long Beach, California
Re: filmscanners: New auto adjust software on it's way
I never claimed their examples had any aesthetic quality, but I do think the software appears to be pretty impressive. Save image 25 or 26 and see if you can get anywhere near the processed example they show you. Steve I admit it is amazing what it does, especially in the saving of images of subjects outside the dynamic range of the picture taking system. 25 and 26 are amazing for creating a picture out of nothing. My reaction was that some of the befores were much more pleasing than the afters. Spy cam clarity at any cost is not always the best way to go. My other reaction was the question, Who is this for? If by some momentary lapse, mini-stroke, or fainting spell someone should produce one of the before pictures, most, on this list, would probably just toss it as they went through the pictures in their hospital bed. Would you have really pushed the shutter button with 25 or 26 in your viewfinder? Winsor -- Winsor Crosby Long Beach, California
Re: filmscanners: New auto adjust software on it's way
No I would not have taken picture 25/26. But many press photographers might like to have the chance to capture a picture such as 25 in the case of a fire at say an oil refinery. Obviously they would want more smoke to remain in the picture but it would be very helpful if you can recognise where it is. There are other situations were high contrast is a particular problem such as a sunset - perhaps you can not only get the full glory of the sunset but also get some detail in the foreground. Normally best exposure for the sky gives a black foreground. If you have your tripod you could do multiple exposures and combine the results but this is near impossible if you have lots of gaps in the foreground.eg. trees in winter. Obviously again if it's too overdone the results will look wrong. If you only ever take studio shots then you shouldn't ever need something like this, but I am sure most other people could find images that could be improved/rescued by a toned down version of this software. Steve Original Message - From: Winsor Crosby [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Wednesday, August 29, 2001 7:50 PM Subject: Re: filmscanners: New auto adjust software on it's way I never claimed their examples had any aesthetic quality, but I do think the software appears to be pretty impressive. Save image 25 or 26 and see if you can get anywhere near the processed example they show you. Steve I admit it is amazing what it does, especially in the saving of images of subjects outside the dynamic range of the picture taking system. 25 and 26 are amazing for creating a picture out of nothing. My reaction was that some of the befores were much more pleasing than the afters. Spy cam clarity at any cost is not always the best way to go. My other reaction was the question, Who is this for? If by some momentary lapse, mini-stroke, or fainting spell someone should produce one of the before pictures, most, on this list, would probably just toss it as they went through the pictures in their hospital bed. Would you have really pushed the shutter button with 25 or 26 in your viewfinder? Winsor -- Winsor Crosby Long Beach, California
Re: Re: filmscanners: New auto adjust software on it's way
Steve said.. Save image 25 or 26 and see if you can get anywhere near the processed example they show you. A quick tip - DON'T try it on the previews, as I checked one of them (the fireman in smoke haze), and it has not got any pixel variation in areas where the processed image shows details! I didn't bother checking the fullsize images. To me, the only clever part is that the software appears to do selective gamma adjustments to areas of the image. However I think the examples are way overdone, especially that awful oversharpening..
filmscanners: New auto adjust software on it's way
From: http://www.steves-digicams.com/diginews.html The software automatically enhances digital images. Samples of what it can do here: http://dragon.larc.nasa.gov/retinex/pao/news/ 8,10,25,26 are little short of amazing. Some of the others are less impressive (22 in particular looks wrong) hopefully there are still some user controls. This is presumably the software they used to spy on us from sattelites and hence is a pure digital system so it probably does nothing for dust, scratches and grain :-( Steve P.S. It's probably a bit slow on Pentium Pro 200's
Re: filmscanners: New auto adjust software on it's way
I have just noticed my lad has been on UT and you have to turn up the brightness a lot. I have rest the brightness to it's usual point and 22 doesn't look too bad after all. Steve - Original Message - From: Steve Greenbank [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Tuesday, August 28, 2001 7:35 PM Subject: filmscanners: New auto adjust software on it's way From: http://www.steves-digicams.com/diginews.html The software automatically enhances digital images. Samples of what it can do here: http://dragon.larc.nasa.gov/retinex/pao/news/ 8,10,25,26 are little short of amazing. Some of the others are less impressive (22 in particular looks wrong) hopefully there are still some user controls. This is presumably the software they used to spy on us from sattelites and hence is a pure digital system so it probably does nothing for dust, scratches and grain :-( Steve P.S. It's probably a bit slow on Pentium Pro 200's
Re: filmscanners: New auto adjust software on it's way
From: http://www.steves-digicams.com/diginews.html The software automatically enhances digital images. Samples of what it can do here: http://dragon.larc.nasa.gov/retinex/pao/news/ 8,10,25,26 are little short of amazing. Some of the others are less impressive (22 in particular looks wrong) hopefully there are still some user controls. This is presumably the software they used to spy on us from sattelites and hence is a pure digital system so it probably does nothing for dust, scratches and grain :-( Steve P.S. It's probably a bit slow on Pentium Pro 200's That is one bunch of ugly photos, before and after. -- Winsor Crosby Long Beach, California
Re: filmscanners: New auto adjust software on it's way
; ^ ) Yes, I can see it might be slow for a Pentium Pro 200! -Original Message- From: Steve Greenbank [EMAIL PROTECTED] To: [EMAIL PROTECTED] [EMAIL PROTECTED] Date: Tuesday, August 28, 2001 2:30 PM Subject: filmscanners: New auto adjust software on it's way From: http://www.steves-digicams.com/diginews.html The software automatically enhances digital images. Samples of what it can do here: http://dragon.larc.nasa.gov/retinex/pao/news/ 8,10,25,26 are little short of amazing. Some of the others are less impressive (22 in particular looks wrong) hopefully there are still some user controls. This is presumably the software they used to spy on us from sattelites and hence is a pure digital system so it probably does nothing for dust, scratches and grain :-( Steve P.S. It's probably a bit slow on Pentium Pro 200's
