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+--- Thread: Turn photo negative to positive image. (/Thread-Turn-photo-negative-to-positive-image)
Turn photo negative to positive image. - RealGomer - 02-10-2022
I've been cleaning out my deceased mother's things and I found some old film negatives. How old? They were taken with a Kodak Brownie camera and the negatives are 2.5" x 3.75", one per picture. It is black & white film. Is there software that will capture these negatives so I can "print" the pictures digitally to share with my brothers? I already have a Canon CanoScan flat bed scanner and GIMP 2.10.30. BTW - Canoscan treats the negative as a negative strip and doesn't capture part of the image. Loverly.
Thank you.
RE: Turn photo negative to positive image. - Ofnuts - 02-10-2022
Home scanners only do 24x36 negatives.
If you want to digitize the negative, the best solution is to take a photo of it with some back light. In the previous century this was complicated (had to find a back light of decent intensity and color temperature that doesn't burn the negative, so that was mostly taping the thing to a window on a cloudy day). But these says you just put the negative flat on a LED display (phone/tablet/laptop/monitor) on which you display a white area (you can insert a sheet of printer/paper as a dimmer/diffuser).
Ideally you do all this with a camera on a tripod (there are also cheap fixtures to transform a phone into some sort of scanner)(*), but if you do this hand-held you can use Gimp's perspective tool to compensate the shooting angle.
Once you have a negative you apply a reverse curve with Curves (ie, make a curves that goes from top left to bottom right) (using Color > Invert would be a first approximation but isn't too likely to be ideal). You can save the Curves setting to apply to further negatives.
(*) If you do this with a camera+tripod there is a trick with a mirror to ensure that the camera axis is perpendicular and centered.
RE: Turn photo negative to positive image. - rich2005 - 02-10-2022
There is a recent GEGL filter Tools -> GEGL Operation -> Negative Darkroom with some settings for these negatives. (had to trawl for this example)
[attachment=7442]
The problem is getting decent back lighting, I have some success taping to window with a-sort-of-diffuser backing. Must try ofnuts tip about using a phone display for lighting.