LG G5 - Confused about HDR 3D LUT calibration

Steve
thank you! It seems to me, that there is a difference between uploading a Unity bypass LUT and resetting the settings to factory default (Reset Picture Mode). After LUT uploading the TV is targeting it's native colour space, after resting to factory default the TV is targeting REC2020. It seems to me, that I made a "reset Picture Mode" before profiling, and after uploading the Unity Bypass LUT. May this be the reason for the profile issues?

Yes, using Factory Reset/Reset Picture Mode will reset settings to factory default calibration, not uncalibrated/native.
Also, uploading a Default Unity LUT only resets/clears the LUT, while any other calibration settings remain.
That is why the User Guides state to use Upload Unity Bypass to clear all settings back to native/null.
So while the drift is bad, that is the real issue.

Also, you can calibrate with a pre-set calibration, but you would have to use a Focused Patch Set, or similar.

Steve

The LG uses a 3x3 matrix to gamut map its native/factory LUT to 2020. No different than what happens in SDR. It is absolutely important that you unity the 3DLUTs located in the 709 and 2020 registers along with the 3x3 matrix. I know users have to unity 709 and 2020 independently but I'm not sure how users unity the 3x3 matrix in ColourSpace . Is that what happens when you hit the Reset Factory Default button?

So you didn't unity the 709 and 2020 LUTs? Post #9 has basic instructions on how to calibrate HDR. Try the instructions and post your results.

Just to add a final comment - HDR LUT based calibration is not that difficult, so long as you manage heat related drift.
And you can do all you need just with ColourSpace.
Info on the LG TV User Guide.



Steve

Thanks DNice,

post #9 in this thread was the key to getting a 3D LUT going for HDR and Dolby Vision on my LG G5 display for the first time.

Wolf91074, you might try extending the stablization time from 3 second up to 6 or 8 seconds to minimize drift. I use an i1D3 which needs the patches on screen longer than the quicker meters used by the professionals I did my HDR and Dolby Vision profiles with 8 second stabilization, the drift plot was completely smooth. The profile time was very long, but the display had the time it needed to return to a consistent temperature between readings. Consistency improves the profile.

LeRoy

The method is only valid for HDR. Dolby Vision is different

DNice
Oops, thanks for the heads up. Too bad I am locked out of calibration on my G5 right now.

Would you care to share what is different about 3D LUT calibration for Dolby Vision?

Thanks,

LeRoy

I will be posting a guide as soon as I have time to write it up.

DNice
Very nice, thanks

Appreciate all the information in this thread. It's extremely helpful. Thank you!

Hi Ted, DNice, tallLeRoy,
Thank you very much for your valuable advice. Unfortunately, I updated to WebOS 26, so 3D LUT calibration isn't working right now. I'll check back in once the problem is fixed.
One more question for tallLeRoy: What values do you recommend for patch size, stabilization color, and background color?

Hi Wolf91074

I run patch size L32, closest to 10% on my WOLED displays. My stabilization is set to 8 seconds FW with Hue 160, Sat 0, Lum 19. Background during measurements is black. The eight second stabilization helps the panel cool down after my slower i1D3 meter keeps the patches up for an extended period. My drift patches are near perfect, but the profile takes a lot longer.

tallLeRoy
Hi

Thanks for sharing information of excellent thermal stability of recent LG G-series. It helped me realised that my older C-series OLEDs (without heatsink) have thermal stability issues that are very hard overcome and I should probably use manual calibration methods for those picture modes that needs maximum 'OLED brightness' setting by design or dictated by viewing environment.

1x LG G-series OLED is now added in my long term wishlist. I think this is one of numerous scenarios that makes consumer happy that calibration software don't have yearly licence fees.

Ville

tallLeRoy
thanks a lot for your information. I will try as soon as possible