Comments about Off Brand Sigma 10-20 4/5.6 F/nikon Dig Slr's:
I read about this lens "finish" and its poor "lens caps" - these things are not important at all to the image. The image is remarkable. Yes, the lens is slow, but at these focal lengths, easily hand held. Looking at exposures under microscopes is fine for those who have forgotten why they take images in the first place. Does this lens demand "thinking" and "composition". Yes, that's why one gets a lens like this. 10mm is where you want to be using this lens in the first place, the rest just helps composition.