TV picture doesn't look as sharp/colourful at 4k60HDR as it does at 4k50

LudicrouslyLiam · April 18

TV is a Samsung UE50NU7470 on the latest firmware, using an RX 5700 in Win11 on the latest driver via HDMI. When I select 60hz within windows both the OS and the TV will say it's displaying a HDR signal but it doesn't look as detailed, vibrant and bright as it does at 50hz. Like somehow 4k60 manages to look less colourful and detailed than even 1080p50, looks flat and grey you can see it as soon as you change it even just on the windows display settings screen. Not that I'm an expert on what HDR is supposed to look like but it doesn't look appealing so I assume that isn't the HDR working as intended. Strangely going to 30hz has the same effect 60hz does, but every other refresh rate up to and including 50hz looks good.

The really strange thing is if I select a higher resolution than native (4096x2160) the picture looks good at 60hz. It's what I'm doing at the moment but of course that changes the aspect ratio so not ideal.

Any ideas what I'm doing wrong!? I've tried every colour space/colour depth combination within my GPU driver, making a custom resolution with CRU - even bought a HDMI 2.1 cable to rule out any bandwidth issues. I can only assume it's quirk of the TV but it has all the correct settings as regards to HDR.

emosun · April 18

Hdr is subjective is the answer. You have to prefer hdr to begin with or it's a non starter.

I actually don't prefer hdr and never seen a screen where it looked good , always looks washed out and overly brown.

Electronics Wizardy · April 18

What is the chroma sub sampling set to? Often HDR kicks on 10 bit, and it needs to reduce chroma subsampling to keep the data rate down.

Doobeedoo · April 19

It's not OLED so a wash anyway for HDR though. Get OLED if you want solid HDR experience.

LudicrouslyLiam · April 20

Okay so I realised after testing a bit more that the effect I'm trying to describe has nothing to do with HDR (although it is more apparent when it's on). I know I didn't take the best comparison shots but hopefully you can see the difference in sharpness or contrast, if you look at the fence lines or the stone detail on the house or even the crosshair itself. The only thing I'm changing here is the refresh rate. It's like a setting on the TV gets automatically changed - game mode is on and I looked through the settings to see if anything changes but for the life of me I don't know what it is.

(and btw this is at 4:4:4 RGB 8 bit, doesn't seem to effect anything even going to 4:2:0 10 bit)