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?