P: Presets with Masking Control Over Develop Parameters

Your approach makes sense and clearly works well for your workflow — but what I'm proposing is an expansion of the toolset, not a replacement for existing methods.

Let me describe a concrete scenario that illustrates the need. I'm editing a large shoot: cropping, exposure, white balance, etc. I export a color version. Now I want a B&W version with specific contrast — particular shadows, blacks, and curve adjustments. If I apply my B&W preset to a virtual copy, it simply overwrites my existing exposure and contrast corrections, because presets replace values rather than add to them. With preset masking, those B&W adjustments would be applied on top of the already-corrected image, not instead of it.

Another use case: batch-applying relative adjustments based on client feedback. Instead of setting red saturation to a fixed -10, I want to apply -10 relative to whatever value each individual photo already has. The same for vibrance, or any other parameter. Preset masks would make this possible too.

And beyond these two scenarios — preset masks would allow combining multiple presets and adjusting their intensity independently, opening up a level of composability that simply doesn't exist today.

Thanks for the suggestions! I'm aware of both workarounds, but they don't quite solve what I'm after — let me clarify.

On virtual copies: yes, that helps avoid re-importing, but it still means managing a separate image. What I want is to apply a B&W preset within the same edit, scoped only to specific parameters (like B&W mix and tone), without it touching my color settings. A virtual copy doesn't give you that — it's still an all-or-nothing preset application on a duplicate.

On selecting parameters when creating a preset: yes, you can exclude parameters when saving a preset, but that's a one-time decision baked into the preset itself. What I'm proposing is different — the ability to define at the moment of applying which parameters a preset should affect, essentially using it as a mask. This way the same preset could be applied narrowly in one situation and broadly in another, without needing to maintain multiple versions of it.

To put it simply: think of a preset-mask as an additional layer sitting on top of all your existing Develop settings — separate from them, not replacing them. Just like how adjustment layers work in Photoshop. Your base edit stays completely intact underneath; the preset-mask only contributes its own scoped parameters on top. You could toggle it on and off without disturbing anything else in your edit.