By: touristguy87 (02-Aug-07)      Experience with product: Not specified

Strengths:	Speed and focus accuracy, image quality, sharpness, moderately priced
Weaknesses:	55mm is a little short but for about 80% of the shots that I want to take it is long enough

Full User Summary
First, I would rather have something more like a 20-135. Beyond that this lens is the best that I have tried out of the 17-85 F4 and the 28-135 F3.6. I think the F2.8 is almost required to get decent focus accuracy and reliability. It may not need to be a *constant* F2.8 but at least at the wide angle it should be F2.8. The short porch is very nice, makes it easy to shoot whatever you are standing in front of, the 28-135 is just too long for this. The only thing this 17-55 leaves me wanting is another 2x or so of zoom range. It would be great at 20-100, even. Wide-angle at night only works for close-up subjects, and the 55mm limit means a lot of walking around to get a good crop on the shot. And you can't use "digital zoom" if you don't get a good focus, so with the Rebel XTi and just about every lens that I've tried, I can't rely on getting a good focus at high zoom. Sometimes it works, sometimes not. But otherwise, I think this lens is worth the $900, the 17-85 is worth the $400, I'd stay away from the 28-135 and the kit lens is not all that bad for "free". What I really want, now, and I guess I'm going to have to wait for, is a good-quality 20-120 or so, F2.8-F4.5ish lens with IS. There is no point in getting a lens that will not focus reliably. Now as far as speed...I've shot this camera handheld at night at full zoom and gotten good shots, plenty of times. Pick your poison: ISO1600 RAW to ISO400 jpeg, it'll do it for you.

By: jyarza1 (08-Jul-07)      Experience with product: Not specified

Strengths:	constant aperture, IS, USM, IQ
Weaknesses:	vignetting, pricey

Full User Summary
I love the constant aperture and IS. It's awesome for indoor handheld shooting. I wasn't used to such a wide aperture so it's easy to overdo the shallow DOF and have part of you subjects face (eg ears) out of focus when that wasn't your intention. It also takes great landscape and night photos. However, as expected for very wide angle lens there is some vignetting at the wide end but not usually a problem. However, becomes a major problem when using the lens hood between about 17-20mm against a bright uniform background (eg blue sky). it also seemed like the polarizing filter might have made it more obvious (?). Anyways, not a deal breaker of course but just something to be aware of. Others on the web have reported problems with dust. I have not had any dust problems after a month or so and I don't do anything special to prevent it. Overall a great lens. Blows the 18-55mm kit lens away.

By: klut (24-May-07)      Experience with product: 6

Strengths:	sharp, UWA to normal zoom coverage
Weaknesses:	price, size (it's pretty bulky), EF-S mount only, no hood

Full User Summary
This is one of the best EF-S lenses available on the market at this time. Lens is pretty sharp throughout, although it vignettes somewhat at 17mm. The price is a killer - $1000 for a non-L lens is just expensive. Build quality is average as well - it's not bad, but can't be compared to L lenses. I often use this lens as a general walk-around lens, although it is a bit too bulky for my taste. There are a couple of comprehensive reviews available on the web, so if you're considering buying one, check them out and compare to some other EF-S lenses. One site that comes to mind is www.slrlensreview.com - has a handson review,

By: gudeng7 (07-Sep-06)      Experience with product: 15 Days

Strengths:	Great optical performance (comparable to L series), wide open at f2.8 for background blur, IS is a huge plus.
Weaknesses:	Price is too high, no lens hood included, zoom barrel not smooth enough, construction not as good as L series, fit only EF-S mount cameras.

Full User Summary
I have been debating for a long time whether I should go for EF-S 17-55 f/2.8 IS or EF 24-70 f2.8L. The EF-S 17-85 is a big no-no because of its poor optical performance. My major concern on 17-55 is that it only fits EF-S mount cameras, which means it will have to go when I upgrade to a full-frame camera body eventually. However, there just isn't any walk-around lens (on a 1.6x crop body) from Canon out there that has f2.8 and IS. I love the solid construction of 24-70 f2.8L and the fact that it can be used on any Canon cameras. However, lacking IS finally pushed me away from it. As other reviewers said, 17-55 has great optical performace. No doubt about that. It complements my 70-200L quite nicely. However, I did notice that the zoom barrel is not as smooth as 70-200L, and the overall construction seems less solid. For the high price Canon charges, we don't even get a lens hood! But anyway, I have no regret that I purchased this lens. There are certain imperfections but I can live with them. This is the best walk-around lens with f2.8 and IS on a 1.6x crop body.

By: nickyfastbid (01-Sep-06)      Experience with product: 2 Weeks

Strengths:	Fast USM AF + f/2.8 + Bullet-proof IS = shooting in all kind of conditions without hassles/tripod/flash.
Weaknesses:	Pricey, not dust/weather sealed, flare control could be better.

Full User Summary
The first thing you will notice is the sharpness of this baby. It's sharp @ f/2.8 through the range, and much sharper than EF17-40L through f/4-f8 especially in the corners. Amazingly it still holds its ground till f/16, that?s nearly Macro lens territory. Sharpness wise this thing is nearly as good as 50mm prime lens, certainly in the best group of L league.Color and contrast are very good @ all apertures, color reproduction is the same as EF24-70L/24-105L IS. This means it is a tick less than EF17-40L, but for me this is just right. EF17-40L is a landscape lens with very high contrast and highly saturated color, use it for normal street photos or portrait can be a nightmare, and you have no way to fix it in Photoshop.Let?s talk about the main feature ? Image Stabilization (IS). Many people say IS only works well for long telephoto lens like 70-200mm or 100-400mm, on mid-range it is not as useful and not as effective ? They Are Wrong. With F/2.8 and 3 Stops IS on hands on my 20D, I can handle the trickiest low-light condition, even EF50mm f/1.4USM prime won?t survive in conditions like that. That is because, 17-55mm f/2.8 + 3 stops IS = 17-55mm f/1.0 in low-light!!! What?s more, IS will mimic your handshake no matter how tired you, therefore the shooting results become more consistent through a long trip.For those who have EOS 20D/30D DSLR, a lens with f/2.8 or faster aperture will activate the double cross AF sensors in the center result in 3 times more sensitive Auto Focus, cheaper EF-S 17-85mm f/4-5.6 IS won?t get such benefit.For those Canon 20D/30D/D Rebel/Rebel XT/XTi users, who want a truly high-performance walk around lens should seriously consider this baby. It does all things to the highest standard in all conditions. $1100 is a lot of money, but for what this lens is capable of, this is going to be a very good investment.