I have a curves adjustment layer, and I want to limit it so it only effects a certain color range. My initial thought was to create a Black and White adjustment layer, turn up the channels corresponding to the target color range, set it to multiply blend mode, and tie it to the curves adjustment layer. Unfortunately, this applies the B&W adjustment to the output of the curves layer, instead of modifying the curves adjustment itself.
I am essentially trying to replicate DaVinci Resolve's qualifiers, which allow you to select HSL color ranges that an adjustment applies to.
The Select -> Color Range tool is also similar, except that it selects specific pixels, and requires you to update the selection any time the base image changes. It also does not let you edit the selection--you have to recreate it from scratch if you want to change it.
You could think of the desired effect as a "smart mask" that would allow me to base the opacity of the Curve Adjustment layer on the underlying color, even as that underlying color changes.
Any idea on how to achieve this?