IF YOU CAN PAINT A GOOD NATURAL FISH, YOU CAN paint a good reproduction fish. The only difference in painting the two is the prep-work required on a reproduction prior to coloring. A skin-dried fish ready for painting has a natural tone that combines varying intensities of gray, brown, and black (undertone coloration). Even though all the color of a fish disappears during the drying, this natural undertone coloration remains and provides a textured background over which transparent colors are applied. This undertone is known as the vermiculation-patterning and provides the patterning that makes a painted fish look natural.