FerrumPix: Photo/RAW-Editor, Viewer, Gallery, Immich and Nextcloud Client in one App

Hi, thanks a lot, and glad you’re enjoying it!

Good catch on the tone curve, and no, that’s not how it should behave. The curve is stored as a straight line by default, but the way the ends of the curve are calculated makes it look like a slight S-curve. As long as you haven’t added a point, that S isn’t applied to the image at all, so the display is simply wrong there. Once you add a point, though, the curve is applied as drawn. That’s why darkening the shadows gives you that odd shape and a stronger effect than you’d expect.

I’ll fix this in the next version.

Regards,
Patrick