Unfortunately, I have the Panny 420 which is only HDR10 capable so I can’t intelligently comment on the proper setting for the 820. Perhaps one of our members with an 820 can chime in here.
Hi Mike. Chroma 4:4:4 is only useful if you’re gaming or using your display as a computer monitor. You could be experiencing video playback issues because of the much higher bandwidth required for 4:4:4. For movie watching, chroma 4:2:0 is standard.
Here’s a Rtings explanation of chroma sub...