* Prices may differ from that shown
I am a big fan of Canon lenses, some are cheap but offer great value compared to other brands and some offer great quality and evan better performance. This lens may be out of reach for the average photographer, but if you can, go for it. This lens has canon's mid-level build quality, a step above the type of lens you get free with your new camera, just below canon's highly respected pro line-up - it feels silky smooth and sturdy. It is above average optics for a mid level lens and a very useful focal length range. Most importantly, it is also a nice fast(wide apperture) lens.
If your not the photography geek I am and you wonder why pay so much for this lens when canon already has the 18-55mm f/3.5-5.6 at a drastically lower price, covering the same focal range, the answer is this: Quality, Brightness and Depth - this lens has all three of these in abbundance.
Having a lower "f" number means the apperture can be wider, this means more light can be allowed into the frame to make dark rooms brighter and background more blurred to draw focus to the subject. If you have ever wondered what is the x-factor that makes magazine photos look a cut above the rest - besdies the photographer - its the quality of the lens and the 'F-stop'
Optically this lens allows surprising little flare (glint from brght objects) and is quite good on the Chromatic Aboration front, with a slight blue fringing near the edges on my copy.
You do get a noticable vignetting effect (dark corners) when at wide open apperture at 17mm.
Focusing is very crisp as ussual with canon ring USM motor.
In one sentance, this is a great generaly zoom that ussually gives me a warm smile when I see the results.
The only downsides are:
55mm is sometimes limiting and I do find myself hovering around the extreme ends of the focal range where all lenses perform their worst.
EF-S - this is a lens that will only work with consumer cameras, so if you upgrade to a Pro 1D or 5D you can't use this lens.
The lens extends quite a lot when zoomed in which will always need to suck in are to fill the void when it enlarges, this has a repuation for allowing dust behind the glass which is a known issue for this lens but not one that should put anyone but the most adventurous user off.