Some details. I decided it might be instructive to see them at close to the output resolution, so I made comparison files on the Epson at 4000dpi. It turns out that the DSLR files needed to be reduced to 87% to match. These are screenshots from a 24" monitor, so they're reduced here by more than 50%. I might put up some full res sections if there's any interest.
See if you can tell which one is the Epson...
Good stuff! I'm going to guess that with the first one the dslr scan in on the left. With the second and third one, the dslr is the right frame, and with the last image the dslr is the left frame, at least I hope so.
Dust is going to be a problem with color materials, since ICE works pretty well with them, and it's very unlikely that we'll be able to get something like ICE working with a dslr scanner, although I'd love to be wrong about that. With BW, the problems should be about equal, given an equally diffused light source.
“You often feel tired, not because you've done too much, but because you've done too little of what sparks a light in you.”
― Alexander Den Heijer, Nothing You Don't Already Know
Well, if there wasn't going to be at least some improvement, I might just have given up, and not posted anything-
The Epson is much more diffuse, even without ICE, which I never use.
One possibility is to introduce another diffuser, below the negative stage, perhaps about an inch below. That might work...
Anyway, that'll be for another time. This has been an interesting exercise, but the scan I made equates to a 5' high print at 360dpi, and I don't get to make many of those from large format. It's good to know that it's there, and can be made to work, but I doubt it'll get very much use- but you never know...
Joseph,
I really appreciate that work you've gone too. Thanks!
“You often feel tired, not because you've done too much, but because you've done too little of what sparks a light in you.”
― Alexander Den Heijer, Nothing You Don't Already Know
Thanks Peter-
So, apart from yourself, there doesn't appear to be any interest in this thing- but I'll post these here anyway, for the sake of completeness.
I'll post them in your comparison thread too-
These are screenshots of a 4000dpi V750 scan against a background of the DSLR stitched output, as outlined above.
They're about 600kb each, and obviously, not cleaned up at all.
For the sake of those who might not have been following, the originals were taken with a reversed 35mm lens, not a dedicated macro optic, so there's a lot of room for improvement.
http://img209.imageshack.us/img209/1...omparison1.jpg
http://img220.imageshack.us/img220/8...omparison2.jpg
http://img717.imageshack.us/img717/5...omparison3.jpg
http://img714.imageshack.us/img714/1...omparison4.jpg
Joseph, there are lurkers interested too. Well, at least one.
Thanks for your efforts.
Make it two, really interesting thread.
Ian
Thank you, two is good, three including Peter...
What I like about these prototypes is that as new models of DSLR are brought out, the sensor portion of the scanner cdan be up dated or improved. For example: Nikon is rumored to have a 36 MP pro-sumer body waiting for introduction "soon".
Drew Bedo
www.quietlightphoto.com
http://www.artsyhome.com/author/drew-bedo
There are only three types of mounting flanges; too big, too small and wrong thread!
I'm not sure that more pixels will improve things-
In fact, I think the 12Mp full frame is a kind of a sweet spot. Not the only one, however...
Already, the scan here represents around 350Mp, and it's obvious that those pixels aren't the best quality.
Trebling the number of pixels isn't going to improve the image, but will treble the file size.
You could choose to image at a higher magnification, leading to more film detail, again at the cost of a bigger file size, but there comes a point where you're imaging the grain, or dye clouds, and not the image-
The image can be improved- by the combination of-
1. Using a better lens- flatter field, less distortion, higher resolution at larger aperture.
The lens used here was at an indicated f/11, probably somewhere north of f/16, taking account of the magnification- so probably at the diffraction limitation of the sensor.
2. Scanning a flatter original- especially at larger apertures, and higher magnification, depth of field will decrease. If you're only scanning flat film, then this is not much of a problem, but not all film is flat, especially if it's clipped into hangars for processing, as is the case with the image above- Drum scanning involves taping the film to the drum, then encapsulating it within another stretched sheet, and something like this might be necessary to flatten the film, to place it within the depth of field of a faster lens.
If those two conditions are met, then a number of further options are available.
You could choose to scan at a lower magnification, leading to increased depth of field, a larger available aperture, and smaller image and file sizes for the same level of detail-
this is probably the preferred option for prints that aren't going to be enlarged more than about 4' on a side.
If you do feel the need to go larger than that, then scanning at a higher magnification might be an option-
A 36Mp sensor could have advantages, in that you might hit the same quality threshold using a smaller number of less magnified higher resolution tiles, but since there is no physical limitation on the number of tiles used to make up an image, pixel count on a sensor is not going to be the final arbiter-
In my opinion...
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