Ok, have redone the experiment with snapshot documentation
This time the deltaE values didn't go through the roof as much as last time. The only difference: This time I used deltaE type 2000 instead of 1976.
But still, the LUT doesn't seem to improve the situation, it gets slightly worse in most cases and stays about equal in the best case.
But step by step:
First I reset my wide color gamut QLED monitor (LG 38WN95C-W) to factory settings and first just dialled down the brightness until I have about 100 nits (HDR mode in Windows is disabled, the factory ICC profile is selected).
Then I started ColourSpace on a separate notebook and the Calibration Client on the PC that is connected to the monitor via Displayport.
Here the settings and initial Characterization results:
dE Values for secondary colors (if needed I can provide the screenshots here also):
Afterwards I manually calibrated the display by using the global Rgb sliders and per color hue and saturation sliders. These were the results:
This profile was saved as "AfterManualCalibration"
Now I created two LUTs with mappings from sRBG to the AfterManualCalibration profile, with the MapSpace and PeakChroma algorithms:
I don't want to waste our time with trying all permutations, but I tried PeakChroma with the original min/max contrast settings and MapSpace with remeasuring min/max contrast - not sure what the expected workflow would be. (Probably the latter makes more sense?).
So first I set the Active LUT to the PeakChroma LUT now:
Here the resulting colors (after another characterization run):
(It appears plausible to me that the dE for white is now worse because the min/max contrast cannot be reached anymore with the LUT?)
And finally the same game with the MapSpace LUT - this time with the min/max contrast remeasured:
My approach was proably naive because I manually calibrated the display to the best possible dE values I could - perhaps it might have been better to leave some saturation margin for the LUT algorithm to work? But I wanted to have the results without LUT as good as possible, because many programs won't use ICC profiles, and those should also get good results. (And currently I cannot save and export to ICC with my ColourSpace DPS version anyways...)
But I would at least have expected that the LUT algorithm when it realizes that it cannot make things better at least doesn't make things worse?
(Unfortunately I don't get the results from yesterday anymore - there the dE values got worse up to dE old value+10 - and not better in any case).
Or did results actually get better and dE is just the wrong metric to measure that? Or perhaps my settings were just wrong...
Thanks for reading down to that point - thanks for having a look!