Otherwise quite a lot would dissapear off the map... like danger zones and some airspace!
It does.
As Genghis noted, you need to experiment with the tools you'll be using and the light you'll be using, so you don't need to guess what will happen. When you go flying, you should already know.
If you're going to carry colored light, carrying several colors of light is usually a good idea. Especially for reading VFR charts. Make sure you have white light in there somewhere, too.