How to edit or add new control? i.e. edit separately for each history step...

[Masterpiga (Daniele Pighin)]

@Kam

The recent problem I met for example is in dealing with the negative film.

There was this thread recently documenting a whole workflow based on negadoctor, you may find it useful:

Darktable, Negadoctor, and Flextight: A workflow demonstration

After helping some other users with Darktable’s Negadoctor module, I thought a workflow demonstration video might be helpful for others. It this video, I use Flextight 3F scans but the negadoctor module part is applicable to dslr or other scanning formats. https://tube.hunter.camera/w/peGzgX83EnY8bMPrrnCwc4