Summary: I bought this lens to take on vacations, and as a general walk around for my Canon T1i. I wanted to be able to take landscape shots, have a little reach on the tele end, and the macro was a bonus. I've never purchased a non Canon lens before, but heard good things about the previous version of this lens. First thing I noticed, the lens does not fit onto the camera with the ease that a Canon lens does. It goes on, but required significant more torque, and this worried me.
AF problem was a shame when it took such sharp images
3 March 2013
Summary: Bought this lens from amazon warehouse and was excited when it arrived. However putting it on my Nikon D200 this excitement soon changed to annoyance as I quickly realised something wasn't right. The AF would continually search even when it was pointing at a still object, it was even worse under artificial light indoors. I tried the lens on my spare D50 and the problem still persited. I have since sent the lens back and won't be ordering a new one.
Summary: I'm sure this is a great lens, but the auto-focus system does not get on well with a Canon EOS 40D - specifically the lens spends a lot of time "hunting" for focus. I upgraded from the original non-OS non-HSM version of the lens, but now I've gone back to that lens. Maybe the HSM is just too fast for the older EOS models!
Summary: On a D5100: The autofocus is inaccurate (about 3 inches off each time) and fails in average indoor light. When manually focused at f/4, the results are sharp at the short end. I had the Sigma 150-500mm, and decided to order this (17-70mm) and the 70-300mm as Christmas presents. While the 150-500 is a great lens, the build quality and image quality on the latter two is disappointing.
Summary: I have already sent a review which you have seen fit not to publish, so I'll try again, more briefly. The Sigma 17-70 is simply not worth even half the price and is out performed in all respects by my cheap Canon 18-55 kit lens. Antony Brown.
Summary: I bought the lens in order to replace the canon 17-85 IS. I use for a very short period, because I experienced a front-focus problem. I sent to an authorized service and the calibrated on my canon 40D. For the time I used the lens I found the lens very sharp and well build, on both matter much better than canon 17-85. Focus was on par with canon 17-85. I found a little inconvenient the wide focus ring; while auto focusing my fingers keep blocking all the time the ring.
Excerpt: Это мой первый отдельно купленый объектив, хотя видео профессионально занимаюсь 20 лет (Sony HVR z7) Потратив неделю, заказав в двух магазинах и попробовав 4 объектива сделав тесты и проконсультировавшись с опытными спецами обнаружил (к своему огорчению) что сей девайс откровенно хуже по резкости штатного 2-х рублёвого KIT 18-55 mm IS II.
Summary: Was soll ich sagen: haptisch ein Traum, wenn es scharf ist ebenfalls einwandfrei und der Bildstabilisator funktioniert auch einwandfrei. Warum also nur 1 Stern? Nun: • mein erstes Exemplar war unabhängig vom gewählten Fokuspunkt fast überall scharf. Die Betonung liegt auf fast, da die rechte untere Ecke hier deutlich negativ hervorstach.