Spektrafilm for already tone mapped photos?

betazoid · August 28, 2026, 3:12pm

Hi,

is it possible to get the awesome spektrafilm film simulation effects for photos that are already tone mapped, e.g. non raw smartphone pics? If yes, how? Just pull the contrast lower in color balance rgb/darktable?

Thanks in advance

A

bazdesh · August 28, 2026, 4:12pm

The spektrafilm python app works with jpegs without too many issues, just be sure to set the input correctly (sRGB most of the time), I would also say to disregard the technically correct function of the “cctf decoding” button and just use it per taste as an extra contrast button.

Maybe send in an example of the photos you have in mind, I guess the success depends on how much contrast it has (how crushed are the shadows or how blown highlights), but I am sometimes surprised how much info there is in a jpeg file.

betazoid · August 28, 2026, 4:29pm

Thanks, I will try this.

marcomastri · September 17, 2026, 4:16pm

I tried spektrafilm (the darktable module) with some photos from my smartphone, and yes, reducing the contrast (and maybe the vibrance) in color balance rgb seems to work for me. I sometimes also reduce saturation in shadows, and add some in the highlights… it really depends on how the jpg was processed, so it’s a bit of a trial-and-error process.