Well, I blew it on the green/blue layer. I knew last night it did not look quite right with a very sandy texture. Today the outer couple of paint layers wiped off like dust with a paper towel and then I removed all the masking. It is not the end of the world, I will just mask it all and paint the green/blue again. I think the problem is when I went to less thinner my paint was drying before it hit the surface. Maybe I will go back to 1:1. Any tips form you expert airbrushers on getting perfect coverage?