I have some film scans from a half-frame camera, so each scan contains two pictures (side-by-side).
Some of the scans are consistently overexposed, but by different amounts. For example:
I'd like to manually adjust the exposure on each half of the scan without having to cut the picture apart, since I like the diptych effect.
Is there a way to select a rectangular area using darktable's
exposure module? Or is there another module I should be using? So far I've only been able to select circles, ellipses, and paths (none of which are exactly right.)