Well, I'm almost done making one for my 580EX....I was confused with the mxwphoto's skematics...so instead of angles in my ring, I made it circular.
I'm almost done, but I'm having trouble figuring out how to make this 90* angle.
Hi jcw, sorry for the late reply. I've been busy. Anyway, to let the light reflect 90 degrees, simply angle the reflector at a 45 degree angle at the joint of the "L" shaped flash ring.