Apple TV 4K (2021) - new Samsung TV - settings changes for optimal viewing

Hi there,

We bought the Apple TV 4K, for our old Sony TV - which didn't have many Smart features or apps, the Apple TV 4K connects via HDMI to a an A/V receiver (for surround sound speakers), and then to the TV via HDMI. Its worked really well (although with an annoying problem - see other thread), and I've been really impressed using Apple TV.

We've just bought a new Samsung TV (50" QN90B Neo QLED 4K HDR Smart TV) - and this obviously has all the various viewing apps. However I would still like to use the existing set up via the receiver and Apple TV to take advantage of surround sound speakers, all the set up apps already & the Steam Link app for streaming PC games.

I've not changed anything from one TV to the other, so I was looking for some guidance on whether I do need to change anything, or what settings would be optimal to take advantage of the new TV. For example, the Video format is still set to 1080 SDR, I tried setting it to 1080 HDR, but this just made the picture really 'foggy' like the brightness had been turned up across the whole screen.

Any advice gratefully received.

Thanks

Rupert