At 17-28 mm, the Sigma does not come close to the Nikon. Debt is partly the lack of manufacturing diversification: No sample had a reasonably consistent focus in this area. Mostly caused by decentering significant blur early sat above the middle, often also in a corner or sometimes left or right. But even apart from that reached the Sigma away from the center at any aperture the sharpness level of the Nikon.
Gradually starting at 34, but clearly at 50-70 mm, the influence of decentralization at Sigma diminishes and it is already at full aperture significantly more micro-contrast than the Nikon. Thus, the images of the Sigma appear much sharper, although the resolution of the Nikon does not appear worse. Has the certain flatness of the images at Nikon at telephoto and maximum aperture the Sigma so not (the Nikon brings stopping down by 1 step in this respect very much, otherwise a moderate sharpening). At aperture 8 the difference is not large, disappeared at stop 11.
The autofocus works at Sigma good as the image stabilizer, and it is annoying that the OS after the trigger-tapping so 2 minutes running after what cost electricity without end.
Amenities in addition to the target page in Sigma:
- Cheating at the telephoto focal length: a maximum of 66 mU, rather only 65 mm reaches 17-70.
- At the D5300 with Sigma was no longer with me the repeat function of all keys. You must, and so umpteen times press When scrolling through the menu zooming same key, which is a pain. That there may be problems on the D5300 has Sigma published on its own website, offering a firmware update. There was talk of problems with autofocus and OS (I had to on the trailing not). Whether my copies were updated, but I do not know.
I could not decide for the Sigma me on these results. Is really annoying that Sigma's engineering services due to negligent production again not arrive even with this lens at the customer. Therefore, only 3 points.