Originally Posted by WiFi-Spy
422 and 420 are the only supported formats for HDR10 at 60P for 10/12 bit. You can do RGB at only 8bit. This is a limitation of HDMI 2.0 bandwidth.
No one is disputing that, Tyler, but you have missed the point of this discussion.
We were originally discussing using the S&M UHD HDR disk to determine the correct color space to select on a player. The Oppo 203, for example, allows different color space settings to be selected, and one is likely to be the "correct" setting, given the other hardware in the video chain.
Then someone asked whether the same color space settings should be used for other source devices, specifically the AppleTV 4K. While previous versions of the tvOS allowed the user to select a color space, the current tvOS public beta version 13 no longer has the option to select the color space. When 1080P HDR or 4k HDR is selected, the player automatically selects 4:2:2, which is clearly shown on the "About" screen. When Dolby Vision is selected, the color space is not shown, but one would assume that it is 4:2:2. The point is, Apple has removed the option for the user to specify the color space, so the argument is moot.