I've done a few different versions, including, constant lighting set high at a 45 degree angle and me shooting behind the lights, also tried with lights whine me, have tried with the lights facing straight up with the idea it might create a better disbursement of light but it just created more shadows and enhanced the raised bits on the canvas making it appear extremely dotty, I also read that a polarising filter on the lens could help; it really didn't. The best so far has been using the daylight first thing in the morning with it being overcast.