it out both on several indoors shots under less-than-ideal lighting conditions and was pleased in most respects, and outdoors. very good results on even moving subjects. Really good product, with highly applauding performance. Image quality is simply awesome. 5 stars for that.

Very sharp light weight lens. Wide open bokeh is not bad colours are outstanding. As I mostly use this lens on a Monopod I.S is not a concern but would be nice for hand held. Focus and zoom rings operate very smoothly.

This is one of Canon's best lenses. It is not as wide open as the 2.8, but it still workd beautifully for most purposes. It's construction is superb. The controls are nicely damped, and it feels wonderful. It is a fairly heavy lens, but that means that it is full of good glass.

This is my first L, but I got chance to try with other L lenses including 100-400. But so far this is one of the sharper L lenses. Comparing it with Canon 50 f/1.4, Rokinon 85 f/1.4(boken king), Canon 100mm f/2.8 macro(non-IS) and others for sharpness on 40D, nothing can beat my 50mm f/1.4.

My first L lens and is sharp; I had it exchanged once and the second is really good; Focal length is right for walk around to parks and play grounds in sunlight; I already knew its slower aperture and lack of IS and no complains on that; Good bokeh on longer side

My first copy was not good at f/4, but 1-stopped down, its is razor sharp but I returned for an exchange and got a fantastic(may be it is how it is) lens; No cons for me so far

I LOVE TAKING THIS LENS WITH ME ANYTIME IM OUTDOORS LENS HAS EXCELLENT SHARPNESS & UNBELIVEABLE LIGHTNESS AS WELL!!!

Consistent Output; Durable; Easily Interchangeable; Fast / accurate auto-focus; Lightweight; Magic Lens; Nice Bokeh; Rugged; Strong Construction

Ugh None Here

"This is a fast, quiet focusing lens with ""tack sharp"" quality. This is my first L series lens and the images it produces have more than exceeded my expectations. I would hightly recommend this lens."

The Canon EF 70-200mm f/4L IS USM ($1,349 direct) isn't as lauded as the company's f/2.8 IS lens with the same zoom range, but it's priced about $650 less, making it an attractive option for shooters who can live with a slower lens.

Optical stabilization system; Fixed aperture through zoom range; Relatively light.

Edges soft when zoomed; Adding a tripod collar is expensive

The Canon EF 70-200mm f/4L IS USM ($1,349 direct) isn't as lauded as the company's f/2.8 IS lens with the same zoom range, but it's priced about $650 less, making it an attractive option for shooters who can live with a slower lens.

Clean mean images with this superbly built lens.

Great ergonomics; top IS

f4 might be a tad slower to someone used to f2.8

I bought this lens to replace an older version of the same lens and it is much sharper than the older one. I use this to photograph moving subjects and a fast running son on the track. I have had no issues with it so far.

Durable; Fast / accurate auto-focus; Rugged; Strong Construction