Interactively, often I end up doing the same relative edit to many pictures. For example,
- set the custom white balance on a whitish object that is common to all of the pictures
- change the tint to a value -2 from the current value: select the tint number, down-arrow, down-arrow, enter
Due to light colors changing with the electricity cycle, the initial custom white balance via the "dropper" does not result in a common absolute values but a quite accurate value that floats between 3000 and 3800 for the temperature with a similarly floating tint value.
In any programming language/script, the relative change would look something like
currentImage.tint = currentImage.tint - 2;
From what I have seen, preset files want to assign absolute values to the variables:
tint = 14,
Using LR 5.7, is there a way to do this kind of relative change as a saved preset or an otherwise bulk edit?
tint -= 2,
Without plugin: no.
With plugin: yes.
There is now more than one option for relative preset plugins, but the one I am most familiar with is:
because I wrote it, and it's free. Since it works flawlessly for me, I can recommend it to you as well.
If you want to see other options, just do an internet search for:
Lightroom plugin relative preset
Sweet plug-in! Seems to get me exactly where I want to be.
For the folks not wanting to go with the plug-in route, the "quick develop" tab in the Library module almost does what I want, if I am willing to go with x-5 for the tint instead of x-2.