CHG_CANON wrote:
Actually, the uses for the 2x are more limited than simply any white L lens if you want to retain autofocus. Check the product manual at Canon USA. I believe AF will be limited to an L lens with a native f/4 aperture or wider as well as a 1D, 7DII or 5DIII body. The f/2.8L lenses (white & black) as well as the 135 f/2L meet this requirement for continued AF with (I believe) all Digital EOS bodies. I'd have to check the manual myself to be 100% ....
Also works on the 5D MKII. If I didn't already have one I'd buy it in a flash. That's a very good price!