I have a Sony x900f tv I've been very happy with

Biggest issue is that when there is sky in the picture the sky always looks grainy. Doesn't happen with other white/light colors really. Mostly just with sky or large lightish areas

There are a million picture settings to mess with. Anyone know what might help? Thanks

I've used the settings from this site on a different model TV as a starting point and have been pretty happy.
Lot of variables, but one of their settings might resolve your issue: https://www.rtings.com/tv/reviews/sony/x900f/settings