A good zoom of 15 to 85 mm (24 to 136 mm KB-equivalent), which was previously unthinkable. The options compared to the standard lens (18-55 mm corresponding to 29 up to 88 mm KB-equivalent) are significantly expanded. Often the difference of 3 mm is underestimated at wide angle, but 18 mm are 20% more than 15 mm which is quite a lot. In wide angle succeed interesting shots with close foreground and background sharp. The extended telephoto range is also quite nice, but not so clearly noticeable. The ring ultrasonic motor I cherish, I know the principle already from the analog days. An intervention in focusing is possible at any time and you never have to worry about driving the autofocus have, even if you sometimes accidentally turns on the focus. That's my opinion, the best drive ever. (My old lens with USM has survived extreme loads.) The image stabilization works well and very quiet (compared to other Canon lenses). She is barely audible. The image quality is very good. Even in direct backlight occurred very little reflections. Are In stark contrast and high magnification of images, especially to the outer edge, to see color fringing. Normally, they do not interfere. Only the shading in the corners disturbs sometimes, but it does not appear to me as extreme as it see some reviewers. Correction via software, if it interferes with some games, why the camera does not always enough, is not clear to me. The lens is a bit large and heavy, but that's hardly different. After further use: The quality and the overall optical properties now I found even when used in very good holiday. Only the zoom ring a little too easy, with heavily tilted lens, the focal length is adjusted by the weight, you have to hold the ring. Update 2013: A repair was now necessary to focus was defective. The lens is still my favorite lens. Update 2014: I now have 4 images of a bridge set. Two are with the kit lens (18 mm - 55 mm), the two others with this lens (15 mm - 85 mm) have been made. The images are trimmed in height and otherwise heavily edited, so they do not say much about the picture quality, but only demonstrate graphically how changes the angle of view in wide angle and telephoto position.
