Starting in the early 60's I was a U.S. Navy "Spook" and when we required a camera, we were issued Leicas. I've no idea what model, probably M3's. My own personal camera at the time was a Brownie Hawkeye. Anyway, we were given different lenses to use depending on the job. I recall using lenses up to 1000mm(on a tripod), but we were given smaller ones also. Again, no idea(or I simply can't remember) what they were. The Navy's logic was simple: any idiot can combine two yellow windows and come up with at least a halfway decent shot. But we never received any complaints, or at least I didn't, on image placement in the frame. Now, of course, I wish I had those camera/lenses.