HDR limits color modes?

[jasoncyu]

Hello, I installed better display because I'm using a 4k TV as my monitor for my Mac and I noticed that the text becomes blurry when it's red but not other colors.

Doing some digging, it seems that it's related to the color space and installing better display and when SDR is selected, it gives me multiple options for color space as seen below.

When I select the RGB Full range option, the color issue seems to go away or at least reduce somewhat.

But when I enable HDR, I'm only limited to a single color space option as seen below.

Is there a way to have the RGB option available as well for HDR or is that outside of the apps control?

In case it helps diagnose, I also observe that when high DPI mode is selected, HDR is disabled and no longer available from the menu.

[waydabber]

You can try decreasing the refresh rate and see if more color options pop up. Probably the connection does not have high enough bandwidth to support non-chroma-subsampled modes (4:2:0 sends much reduced color data to save bandwidth, that's why quality suffers). In SDR YCbCr 4:4: is not inherently lower in terms of quality but many displays have trouble converting YCbCr to RGB properly so colors might look bad still.

If you are using HDMI and on an entry level M1/M2 mac, you can greatly improve things if instead of using the built-in HDMI port (which is limited to HDMI 2.0) you use a VMM7100 based USB-C to HDMI dongle.

[jasoncyu]

Ahhh if I plug my HDMI cable to the mac directly rather than a thru a USB hub, I have no issues with red text no matter what configuration, HDR or not. Thanks for the help! I guess my USB hub was the limiting factor

[equinusocio]

I have the same issue, my M1 MBP is connected with type-c to the 1440p monitor directly, but at 120Hz i have only the YCbCr color mode option wich sucks so bad and makes everything blurred. I have to set 60Hz to get 12bit colors. How is supposed to connect to get 10 or 12bit colors with HDR at 120Hz?