Thanks for the info Joanna, I'll look into it. However, I mix the paint very thin, and apply layer after layer, so there are really no visible brush strokes. I could understand that if I used oils, or even if I didn't thin the acrylics, but I thin them so much that I can't even see (very few) brush strokes from 4" from the canvas with my glasses. But when I take pictures, at least with the flash, all kinds of things show up that can't be seen with the naked eye. I'll start googling for some info, and try taking some shots without the flash to see what I come up with.