My Sonex is bright orange, Polyfibre "Pumpkin", and I have been told it is easy to see in the air. On the ground on green grass it is obviously very easy to see but I have done a few flights over terrain that looked like this:
I suspect that if I did an out landing in this landscape it would be as good as camouflaged.
A few years ago I was at the Avalon air show and asked about the paint scheme on the BAE Hawk 127s that the air force uses as advanced jet trainers. The scheme is a light grey/dark grey combination which looks like they are trying to hide the aircraft in a black and white photo. I was told it was to
increase visibility. I might have sounded skeptical at the time.
Peter