Mike, I was just kidding around
The fact is there are so many sample variations around, Sigma might be the champion, but even Sony/Zeiss are not immune, and I personally had to return my 16-35 which was very sharp on one side but less sharp on the other. The new copy is better balanced, but the old copy was sharper (well just on one side
) So for me all these tests are meaningless, because they depend on the sample variations and the subject matter as well. It is not unusual to get better results from one lens over another for one scaene, just to get the opposite results on the next scene. I myself don't care much about sharpness (as in pixel peeping). I have adopted since many years the Zeiss glass for 3 reasons, sharpness is not one of them. In order of importance, they're color, micro-contrast, and 3D. That's what one really sees in a photograph, and that's why I don't use Sigma, or Canon, or Nikon glass (well, I use 2 Sony lenses, but only because I really need to
). It may very well be sharper than Zeiss equivalent, but it lacks the above qualities that I really appreciate.