picture

Yeh the 100-400 stops down as you zoom, so at 400 it's 5.6 wide open. I also have a beat up old Canon 300mm L 2.8. It's so old it was made for the auto focus film cameras. The focus is "off" but with stuff like the 7D I can correct it in the camera menu.

My 70-200 is not the II version

Only way I can shoot with these anymore (I'm weak and shaky) is to crank the shutter speed way way up, us Av