Google promises us a 4K experience, and in Tomb Raider's quality mode, that's what you get - viewed through the lens of a compressed feed, of course. A performance mode is also available which is the preferable way to play, and does seem to deliver a locked 60 frames per second - based on the admittedly small sample we've experienced so far.
The Tomb Raider shots here though are important in that it does validate Google's 4K claims - not to mention that our capturing solution is grabbing Stadia output at its best. The game's general darkness in these areas does help the encoder in maintaining more quality - more bits can be spent on the brighter, more details areas but there is some loss of fine detail in the darkness. Generally speaking though, some clarity is always lost, but the image holds up in motion. It is a 4K video feed, the game is rendering in 4K, but some fine detail is lost. We'll look at the differences in visual features in another article and there are some enhancements, but if there's a blemish, it seems to be a reduction in anisotropic filtering quality.