Reno, you obviously need to do a bit of AF calibration touchup in order to get maximum sharpness out of your images.
I have tried both 1.4xTC MkIII as well as 2xTC MkIII on 70-200 f/2.8 IS MkII, and the resulting combos have a very good IQ. In fact, the 1.4xTC based combo practically eliminates the need for a 300 f/4 prime.
Here are two shots with 70-200 f/2.8 IS MkII + 1.4xTC MkIII, done on 1DsMkII, about 50% crops.
Dec 12, 2011 at 04:25 PM
Previous versions of PetKal's message #10161129 « 70-200 f/2.8L IS MK II + 1.4X II TC »
