I shoot with a 30D and a variety of lenses and I just recently heard of "Trap Focus" and "Focus Priority" which sounds really great for, say, a track race. If I'm on the sidelines, I can set lane 4 in focus over a specific hurdle and not shoot until the runner is in focus right where I want him (within reason since I know the f stop will allow for a range of focus).
I've heard explicitly that Nikons have this and I'd like to believe that Canons do as well. Anyone know how to make it work on a 30D? Thanks!
As far as I know no EOS camera has "trap focus", which is a mode where you are in manual focus mode, press the shutter and the camera waits until something is in focus before it makes the exposure.
"Focus Priority" just means that the camera won't take a picture if it can't focus on something in autofocus mode. "Release Priority" means that the camera takes a picture when the shutter is released, even if it can't get focus on anything.