The sharpness satisfies probably even higher demands, concessions must be made to the image corners and Area Borders only at full aperture light.
The pincushion distortions are clearly visible at the lower end of the focal length range (wide angle), for example when photographing architecture. But the one hand, getting the self-similar (but much more expensive) Canon original lenses often no better way, and on the other hand can be slightly out these distortions expected software from the pictures, you can get on the Internet conveniently.
The workmanship is good and makes a solid impression. The zoom ring can be moved tired and no play, the tube has in the extended state (at 50 mm) only miniales game.
The autofocus is, although here no ultrasonic motor is used, sufficiently rapidly. The only drawback here is that the focus ring rotates in the AF position, which is not necessarily more prior art. Therefore only 4 rather than 5 points.
All in all a highly recommended lens comprises Sigma EX Series at a fair price.
