Coverage can certainly be manipulated, as well as the colors themselves. That's what I've found out doing my test runs. It was no surprise, and was extensively discussed on the net when I was doing my research, Since approximation of originality is the whole point, it's enough to make you tear your hair out when you realize all the variables. But, I'm getting closer with each test.

I prefer wood to plastic, leather to nylon, waxed cotton to Gore-Tex, and split bamboo to graphite.