What happens to a lens when you turn the focus ring during AF mode? I have read that this causes damage, or can cause damage. But what is actually happening? I've done this recently with my Canon EF ...
I have a Canon T3i (600d) and two lenses: EF-S 18-135mm and EF 50mm f/1.8. While working with manual focus, I can shoot out of focus (on purpose) with the 18-135 (as expected). But with the EF 50mm, ...