78% with just 4 color bars. Super fun game. Problem is, I got a 78% score with just 4 horizontal color bars. https://ibb.co/Mpvt1c2 EDIT: why the downvotes?
77% with just two. https://i.imgur.com/qlmmGL9.png
It feels like a solid gray patch with the default color would have a slightly higher percentage but I'm having a hard time getting an even enough spray to say it's from the shade and not density variations between the light/dark portions.
Sadly for me, using single color leaving the middle and top brighter was significantly better than my actual attempts hitting near 80.