My school bought a Panasonic 4K camcorder (which I don't remember exactly which model) pointed at a green screen and this got me thinking.
If it's a HC-X1000 with it's tiny sized sensor and 8 Bit 4:2:0 (In HDMI output too!) it probably means it won't record green screen and subject transition nicely.
So what I wonder is. Is 4:2:0 really enough for chroma key? I have heard even 4:2:2 has problems when it comes to chroma key so I am worried and would like some clarification
Also, If I downscale 4k 4:2:0 to 1080p somehow will it mean it will become 4:2:2 footage? I have thought about trying to do this then doing some recent "Artificial Intelligence Supersampling" wizardry to push it back to 4k