UPDATE: This Experiment is all Wrong. I should hit my head on the same wall I used to measure reflected light off. Some great comments about what went wrong, and great discussion going on – I posted the main points here.
Have you heard about the Inverse Square Law? It’s the law that says that light intensity falls the farther you move your light from your subject. It also tells you that if you move your light to be twice as far it will fall by 4 (the square of 2). if you move the light three times as far, it will fall by 9.
We all swear by that law. The only thing is this law does not apply to the way most of us use flashes.
I’m gonna explain this in a beat, but first here is my newest cheat sheet. (I love cheat sheets. If you are as senile as me, you can print them and then pop them up later and look really smart).