LG C1 OLED 48 as external monitor with Macbook Air M1?

[Mjoshi]

Anyone here using LG C1/CX with MBA M1? Do you get full 4K resolution with it? What connection cable you use with it as LG OLED supports HDMI 2.1. My primary use is for productivity and Image / Video editing.
TIA

 

[joevt]

There are two kinds of DisplayPort 1.4 to HDMI 2.1 adapters. One uses a Realtek chip and the other uses a Synaptics chip. I don't know how either works with the M1 Mac.
Here's a post about HDMI adapters and HDR support.
#21

For full HDMI 2.1 support (4K120 4:4:4), the OS needs to be able to use DSC. I think Apple stopped supporting DSC in Big Sur for most cases? So you might be limited to 4K95 for 4:4:4 10bpc. But there's no way to add custom timings to macOS on M1 Macs so you'll be limited to whatever the OS decides to give you - at least 4K60
https://www.rtings.com/tv/tools/compare/lg-cx-oled-vs-lg-c1-oled/10619/21421?usage=11&threshold=0.10
4K120 is possible with HDMI 2.0 using 8bpc 4:2:0. HDMI 2.0 can't do 4K120 HDR (requires 10bpc).
A DisplayPort 1.4 to HDMI 2.1 adapter can do 4K120 without using DSC using 10bpc 4:2:2.

 

[Mjoshi]

There are two kinds of DisplayPort 1.4 to HDMI 2.1 adapters. One uses a Realtek chip and the other uses a Synaptics chip. I don't know how either works with the M1 Mac.
Here's a post about HDMI adapters and HDR support.
#21

For full HDMI 2.1 support (4K120 4:4:4), the OS needs to be able to use DSC. I think Apple stopped supporting DSC in Big Sur for most cases? So you might be limited to 4K95 for 4:4:4 10bpc. But there's no way to add custom timings to macOS on M1 Macs so you'll be limited to whatever the OS decides to give you - at least 4K60
https://www.rtings.com/tv/tools/compare/lg-cx-oled-vs-lg-c1-oled/10619/21421?usage=11&threshold=0.10
4K120 is possible with HDMI 2.0 using 8bpc 4:2:0. HDMI 2.0 can't do 4K120 HDR (requires 10bpc).
A DisplayPort 1.4 to HDMI 2.1 adapter can do 4K120 without using DSC using 10bpc 4:2:2.

Thank you for your input, I will checkout those adapters for full HDMI 2.1 support