Digital Light & Color

Would it make sense to split the Saturation slider in Adjust\Color Tab to adjust saturation separately for the white and black part of the masked image, in a similar fashion the slider operates in the Saturation transformation?

Theoretically, the split processing could apply to almost any transformation that uses and amount mask. I already have an item on my things to do list for this, but it would be a lot of work to propagate the feature across so many transformations and it would make them all a bit more complicated to master.

In truth, I was just looking for making the Adjust even more flexible - there are quite a few things that are packed into this single transformation - split saturation in Color tab seemed like it could be useful (but then there is Saturation transformation that could already do it - so not a problem).

I'm sure you have considered that already, but if the presence of a mask could split a slider control, maybe some kind of switch (or a third slider 'handle' that would drag them both) at the control level, locking the two split sliders together by default and unlocking when needed, could work to make things easier?

Just one more thought on those split sliders. The Amount slider splits already when it detects a mask, so if the transformation strength is to be different in white and black parts of the mask, that's done.

There are, I think, 3 transformations that start from zero and could be dragged both ways producing different effects: Saturation, Brightness, and Brightness Curve (with the two sets of curves buttons) - for which split effect slider makes more sense than the Amount slider that merely blends the output image with the input with the mask determining the strength of it. Those sliders are already split when there is a mask.