From my perspective:
There are only 2 colors on bad days, or at a distance. Light and Dark. Up closer, you can see the other colors. Once you get to a certain distance, or on days with the right light, light and dark disappear, and you get the whole plane in dark gray. The trick is to understand that it happens, and to try and keep it closer in. When it does happen, you can't panic, and you have to be deliberate in bringing it back to you so you don't lose it. The point is in being aware, then recovering it. I try to use dark color on the bottom, and light color on top, as you roll it, you really see the difference.