OK--I understand the 1/4 is the size of the hole in my camera that attaches to the tripod. the 3/8th is the attachment (maybe the quick release plate) that attaches to the tripod. Then you would attach the camera to the quick release plate that has a 1/4 bolt to attach it to---Right? Some of the Bogen tripods I'm looking at have a quick release plate. Some don't and just have the head with a 1/4 or 3/8th head. Now I have the Rebel XTI and I do plan down the line to get a 5D. I gotta say tho---that line is long
