I think somebody might have once said something along the lines of: if the color isn't helping the image, take it out. But about photos. I suppose in painting you can make the color help the image, so this statement is somewhat invalid. fuuuuuuuuuuuuuuu logic
But I have this art class and I have to do a still life pencil drawing. Considering a skateboard wheel or a ray gun as portrayed in the 40s/50s, if that counts as still life. I'll post the results later, it's probably gonna suck.