I just received the Sigma 50mm 1.4 HSM today, and I just wanted to post some pictures and full frame crops from the two lenses. As you can see, the sigma is much larger than the nikon. On to the pictures (all f/1.4 taken with D3) Full Picture (Sigma) Full Picture (Nikon) Center Crop (Sigma top, Nikon bottom) Remote Crop (Sigma top, Nikon bottom) Lamp Crop (Sigma top, Nikon bottom) Food Package Crop (Sigma top, Nikon bottom) Conclusions: I'm not too happy about the Sigma in terms of center sharpness at 1.4. There seems to be some kind of strange offset in color, that goes away when stopped down a bit and strange optical abrasions. Center crop Sigma at 1.4 and 2.8 View attachment 245745 In terms of Bokeh though, I am very pleased. I was never happy with the bokeh of the nikon 50, and I feel I like the bokeh of the Sigma much better. Anyways, I just wanted to let everyone know how this lens performs, initially. I'll have some time to really use it in the field later, so I'll update everyone as I go.