Lars, you are correct that Canon makes very good lenses. Zeiss and Leica (and maybe Nikon) made slightly better optics, but that's offtopic. I suggest you avoid most Sigma lenses at all costs. Their QC (quality control) isn't very good and many people receive defective lenses. Their optics aren't always that good either. Now, there are exceptions. The Sigma 180 macro lens is just as good (if not better) than its Canon counterpart. Also, in many cases there is a cheaper Sigma lens that does something no Canon lens can do, i.e the 300-800mm zoom. But Canon's 70-200 lenses are the best. It doesn't really matter which one (well, the 70-200 f/4 IS is probably your best bet), but go Canon. Tamron's QC is decidedly better, and I personally would feel a bit more comfortable going with them. But if possible, go Canon [H]


hope this helps.


brendan