Taking a look at the raw numbers, the Apple TV 4K 2021 is capable of putting out video at a resolution of up to 4K at 60 frames per second. That UHD capability is matched with HDR10, Dolby Vision, and Hybrid Log Gamma support. There's a bit of an issue when switching between standard dynamic range (SDR) and HDR content, but Apple provides you with finer control over that behavior in the latest version of tvOS than they used to.