Quote Originally Posted by Alan Stankevitz View Post
Hi Artie, I understand that TC's slow down the autofocus more-so with the 2x but there are variations with certain combinations of TC's and lenses. For example, the 70-200 f/2.8 II lens with a 2x TC is quite fast at acquiring focus whereas the 400mm f/2.8 II lens + the 2x is not very fast. Thanks, Alan
I disagree. I would say that initial AF acquisition with the 2X III TC/70-200 f/2.8L IS is very much on the slow side. And again, I have not used the 300/2.8 II with the 2X for flight....