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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.
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.
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.