I have tested the volumetric probe correction in my environment: LG Oled E8, I1D3, Jeti 1501, Murideo PG. Comparisons have been run between various volumetric corrections and FCMM.
The approach I have used was:
- Measure for corrections based on the native (wide) gamut of my E8
- Validate the correction in the same scenario
- Test the corrections on a Rec.709 Gamut previously generated with LS.
For all verifications I have measured the distance from Jeti to the corrected I1D3, both in math terms (i.e. %dY - normalised on 255,255,255 for easier comparison, dx, dy, dxy) and perceptive terms (dE2000). 1000 (10^3) patches have used.
More detail about my conclusions
- You start having significant improvements with volumetric is based on 4^3 profiles. Volumetric based on Quick Profiles has not given me good results. I see FCMM limitation due the non additive nature of WRGB OLED display has been solved.
- I have tried measuring for volumetric having reference and colorimeter reading at the same time (i.e. using DIP mode). This method has not given me significant improvements, so I have switched to the usual readings, keeping care to do preroll and warming up.
- Using the CMF basic I1D3 profile works badly for Reds. It works using the WRGB Oled EDR profile.
About item 1:
Here below a snapshot comparing Primary Only QP (with a trick I explain later), 3^, 4^, 5^ and FCMM;
Starting from 4^ the correction is interesting
Here also a snapshot of primary and secondary colour down to level 193:
The quality of 4^ is impressive!
The limitation in correction appear down to around 1.5 Nits. This is a difficult area also for FCMM, e and clearly, 11D3 limits take their role. To have an idea about you have to open the attached excel
and have a look.
Regarding the use of quick profile, Steve (@Light Illusion) has clarified me that they must be valid Quick Profile and must be read from the Calibration Interface. So, as I wanted to remove RGB level 13 from Primary & Secondary QP (the validation of Primary only has returned poor results), I have had to run it from Display Characterisation. Also important, for anything it is not a quick profile, you have to start from DC
. If interested I have files I can share with you.
About item 2:
Here below testing outcomes (over 987 most luminance patches) generation comparing readings done at the same and at different time:
There is a little advantage for data taken at different times. If you to have a deeper look go into the attached file
About Item 3:
The herein snapshot, shows how, using the I1D3 CMF profile reflects in a significant Red chromaticity errors, whilst that is not happening using EDR correction and FCMM.
This has been also been confirmed by @liberator72
testing on the same subject.
(dE2000 genius), @bobof
(his patch generator and his advices) and @liberator72
for sharing his testing results