spectrum's reviews

Canon EF-S 17-85mm f/4-5.6 IS USM

What I like most about this lens is how it looks. In my subjective opinion, it's the most beautiful of all Canon lenses, especially among the low end models. With it my camera (450D) looks really "pro". The build is unusually good for such a price, and it doesn't end with appearance - there is the fact that the front doesn't rotate when focusing or zooming. USM makes the focusing fast and silent, and the full time manual focusing is a nice feature.
5X zoom may not seem like much with all those 20X bridge cameras out there, but it turned out to be quite acceptable. I went on a 2-week trip all over the Far East, shot well over a thousand photos, and there were just a handful in which I felt constrained by the 17-85 range.
Sharpness may not be perfect, but nothing that a sharpness filter can't handle. Anyway, I took a photo of the Moon at 85mm f/5.6, and a crater just 4 pixels wide looks undeniably like a crater, even before the sharpening, and with less than perfect focusing.
The lens is not without its disadvantages, however. Perhaps the most bothersome one is the chromatic aberration (especially at the wide end), though it's not that terrible, and, besides, there is a lot of software out there to deal with CA.
Also, it's relatively large and heavy (and expensive) compared to EFS 18-55, which is a decent alternative to the EFS 17-85 (if you don't mind the lower quality build and appearance, and a more restricted focal length range).
But if I had to buy my first lens again, I 'd probably make the same choice. No regrets so far.