I think looking up from below water has a great deal to do with angle. There was a physics problem from my undergrad about the maximum angle you could see through the surface of water from below. Don't really remember anything about it, but if you use the fresnel curve in your material, that should take care of it? I think it's looking better at any rate. Yes, its "Snell's Window". The mia_mat can do that easily. I'll see if I can dig up some tests I did. The blinn and other standard Maya materials would take quite a bit more work since they are not physically based. Falling asleep at my keyboard right now, laters.