For some reason, I couldn't "get" it. I couldn't remember the location of the planes, I kept forgetting them and eventually abandoned learning them. But I knew I had to go back to it eventually because it's vital to drawing; the head CANNOT be properly depicted without understanding how light falls on it which means knowing the planes.
I don't know what happened between now and then but I suddenly understand the planes. I think it's because I'm now relating the planes of the head to what causes the planes which is, of course, the skull! The planes are directly related to the shape of the skull and, to a lesser extent, the facial muscles. NOW it makes sense!
It also helped to use other diagrams in addition to Loomis's. There are various ways to depict some of the planes, some ways more complicated then others. Here's some of the photo reference I've been using to study the planes:
|This is from James Gurney's website. I based my studies of the front of the head primarily on this drawing.|
|These Asaro heads are really helpful for understanding the planes in profile.|
|The Fred Fixler planes, particularly helpful in showing the 3/4 view.|
|Another 3/4 view for studying via the Asaro head.|
As you can see, each of these examples varies slightly. I was originally overwhelmed by the differences. But once I realized that the differences are minor, I set about just absorbing the approaches that made the most sense to me. What makes sense to me is more likely to be retained than pure memorization.