As the sun moves higher in the sky the light becomes a bit more contrasty but with the dunes it can allow shooting for more graphic lines even near mid-day. With this subject I could have played with exposure and experimented easily. The dunes allow for a lot of shooting, especially these, Eureka Dunes in Southern California which rise over 700 feet high. If you don't get the right angle on one you slog through them to another. Light is Everything Copr.
All photographers are dependant on light to create images.
It may seem evident and not worth mentioning as we all know that without light we don't have photographs. If you want to test this one, it's easy. Go into a cave and shoot all the film you want without light. Then try it with the lens cap on. See if you can tell if any are over or underexposed.