New Sigmoid Scene to Display mapping

[paperdigits (Mica)]

@OK1

Th authors of sigmoid and filmic may wish to include this tip in the documentation, and in their demonstration videos/ comments on forums, as I have found this use of the tone-eq, to be a lifesaver, in the interim period, where we do not have a suitable scene referred compatible shadows and highlights module.

We already talk about using Tone Eq instead of Shadows and Highlights here: https://www.darktable.org/usermanual/en/overview/workflow/edit-scene-referred/

I don’t think we’ll get a scene referred Shadows and Highlights module because, as you mention, Tone Eq can do what S&H did and a lot more.