Thanks for your quick replies!
Quote Originally Posted by Busted Knuckles View Post
I have the config you are discussing and like it quite a bit.
Busted Knuckles, what do you think about image quality with extender at full focal lengths? What about auto-focus speed that by spec will be slower? Is it really noticeably slower? I understand that extender will take me to f/5.6 which is enough to auto-focus my 600D, but what If I will stop down a little more, lets say to f/11? Is auto-focus going to work slower or it will not work at all? Or it will open aperture to f/5.6 to auto-focus and then go back to 11 to take a shot? What are your thoughts on shooting wildlife with extender?