Hi all,
I'm calibrating Dolby Vision on an LG OLED77C6 (2026, C6H, Primary RGB Tandem panel) with ColourSpace ZRO, an i1 Display Pro (LG 77C6H correction) and PGenerator 1.6 (DV Calibrate / DV Verify), following Ted's DV guide. The TV accepts a DolbyVision_UserDisplayConfiguration.txt via USB.
Since ZRO can't save profiles or generate the config automatically, I'm building the file manually, and I've found some issues with these new panels:
100% primaries in DV Calibrate are white-boosted. R 0.624/0.369, G 0.412/0.501, B 0.181/0.267 (blue 521 nits), with both 10% and 29% windows. At 50% and 75% stimulus they are clean: R 0.6821/0.3156, G 0.2629/0.6959, B 0.1506/0.0559.
Using those 75% values in the config, saturated colours in DV Verify went outside P3. The DCI P3 primaries then measured R 0.6881/0.3098, G 0.2484/0.7052, B 0.1493/0.0453, which look like the true native primaries and are very close to a G5 config calculated by ColourSpace HTL that another user posted (0.6886/0.3104, 0.2436/0.7142, 0.1484/0.0460).
A second upload with those native values improved DV Verify clearly: Filmmaker EOTF went from +20% to +8% over PQ, and the ColorChecker ΔE ITP (colour + luminance) went from 8.1 to 4.6.
Questions:
How does ColourSpace HTL/XPT calculate TPrimaries and Tmax for the Dolby config? From which patches and stimulus levels?
For ZRO users on these tandem panels, is measuring the P3 primaries in DV Verify after a first upload an acceptable way to get the native primaries? Is there a better manual method?
For Tmax, should it be the peak white with a small window (10% reads ~2300 nits here, beyond my i1D3's reliable range), and with LG's "Peak Brightness" setting off?
Thanks in advance! | 