Hi there! So I have a D7000 paired with a sigma 17-50 2.8. Im on a trip in Canada and the only lens I brought is that sigma, as my main all-rounder. I took these photos aiming always at her face. AF-S always. Handheld. Very calmly, not rushed pics. Aperture mode, f2.8. http://i41.tinypic.com/k1cnpl.jpg I tried taking both pictures with the focus square moved to the side she was, as well as having the focusing square at the middle, focused her face, half press, recomposed, press all the way. I have to say that I have tested the lens with the coin on the ground thing, looking for bad focusing issues and at the time, all went good. Im not sure I did the test in the right way though. Also, with my other lenses, like the stock 18-105, I didnt remember having something similar. What is the deal? Camera defective? Lens defective? Do I need to tweak any settings? Is my technique bad?