ive only seen this happen 1 time,so its very very rare. a guy was painting the boot stripe on a yacht,maroon was the color. when he finished spraying,he had a ton of fish eye. as the paint was not dry,he wiped the paint off with reducer. then he painted again.., same thing.we were both pulling our hair out,he wiped the paint off again. and i tried to paint the stripe using my gun and compressor. came out nice no fish eye. then i used his gun and my compressor on another panel. no fish eye.the only thing different was the compressor.. he pulled the compressor head down and found oil on top of the cylinder head..the rings were bad,causing the oil to be sprayed out with the air.a new compressor cured the problem...