color calibration - same settings, different results

I have noticed that if you adjust RGB or other settings in color calibration you get one result in color change, but if you reset color calibration and make the same changes in a new color calibration module, you get a different result.

IMG_7808.CR2 (28.4 MB)

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Here are color picker readings for some adjustments made to the blue channel using the color calibration module.

After resetting color calibration, the same adjustments were made to color calibration 2.

IMG_7808_01.CR2.xmp (7.9 KB)

The difference is small in this example. However, I noticed significant differences in images that I was going through some edits history stack in which the original poster had made all changes to color calibration in the original module, but I made them is a second module. I discovered that to make my edit look the same as the original, I had to make the changes in the original module.

Why would there be a difference?

It’s because the adaptation setting in the CAT tab is not the same.


Looks like whenever I want to use more than one cc module, I should make the adaption settings the same. I don’t know if that is explained anywhere, but I missed it if it was.

Thanks, Donatzsky!

Using it as a channel mixer set to bypass and make your changes…if you do it in the first instance it is becoming part of the CAT of the WB settings… it may be subtle… I think its good to just leave one instance to deal with the wb and then a separate instance (s) for color… the best reason to do this is because if you want to toggle the module to see the impact then you cant really do that with one instance

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I don’t think there’s any reason why they should be the same. Simply use whatever gives the result you want.

And as @priort says, it’s simply good practice to use separate instances for WB and other corrections.

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The issue I was having is that when someone made all his changes in the original cc, I would try to put them in a second module, to do what you, @Donatzsky and @priort, recommended, and what I have watched Boris do a million times. Except it didn’t produce the same results. Now I know why.

I agree that when I edit, I will keep doing what I have been doing, and leave cc set to bypass.

Rather, if you reset the first instance of color calibration, you also reset the CAT values, i.e. the white balance settings. The visible effect of that can of course vary. So if you want to transfer the non-CAT settings to a second instance, you have to make sure to keep the CAT setting in the first instance, and reset everything else.

A second instance should have the CAT set to bypass, otherwise you’d apply the whitebalancing twice (usually not a good idea).

I also prefer using one instance for white balancing, and additional instances for other work. But in OP’s case, he started from playraw sidecars where he wanted to create that separation…

As much as I give that advise I get lazy… I find the sliders in colorfulness and brightness really nice to quickly tweak the sky and more often greens like leaves and foliage… so I often go strait there…but if I want to re-evaluate I kick myself as then I am zeroing sliders and not just turning a module on and off to see what I am gaining or losing with this part of the edit…

I just tried, and it doesn’t seem to have any negative effects. As long as the illuminant is set to same as pipeline there shouldn’t be any issues (indeed it complains if it’s set to anything else).

New instance are normally created in bypass so there shouldn’t be issues unless somebody duplicates instead… and your suggestion is also noted in the manual…

  • By default, if an instance of the color calibration module is already performing chromatic adaptation, each new instance you create will automatically have its adaptation set to “none (bypass)” to avoid this “double-correction” error.

The chromatic adaptation modes in color calibration can be disabled by either setting the adaptation to “none (bypass)” or setting the illuminant to “same as pipeline (D50)” in the CAT tab.

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