9 out of 10 points and recommendedUseable at near-max aperture, high-speed low-dragAF accuracy in sub-optimal light
This is a splendid little lens which has forced me to be less lazy on my feet. I like it as an indoor lens when quarters are tight and the light is low. It improves dramatically from 1.8 to 2, and I find that I can achieve a good number of keepers at that aperture — better to have a little less sharpness for the sake of the shutter speed, but really, f/2 produces quite good quality. Above about f/5.6 it's impressively sharp (or f/4, by the SLR gear tests). Its small size make people less unsettled by the photographer's presence, especially when he's up close getting a tight shot with a short lens.reviewed December 31st, 2006
Autofocus is another issue. I'm not sure if it's the lens or the body (350d), but at distances of over eight or ten feet, focus precision is really inconsistent. Perhaps it's because of the stage lights, or maybe the subject was isolated enough from the background; my EF-S 17-85 is more accurate and hunts a bit less at 28mm given the same conditions. Nonetheless I only feel comfortable using this lens at close range. The wideangle nature combined with a small viewfinder makes it very difficult to manual focus in conditions where the autofocus won't do. I know available light is tough, but this is the sort of lens designed for such situations. As usual, good light solves the AF issues.
10 out of 10 points and recommendedFocal range, IS, all-day portability, image quality (especially for the size)Temperamental focus ring, wide-angle barrel distortion
I don't have any experience with Canon L, but I like this lens a lot. It's quite good at maximum aperture, though at the wide end I suppose it gets a little soft. Moreover, chromatic aberration can be a problem at ~17-20mm. However, this lens, combined with a Canon CMOS, and compared to some cheaper lenses, produces technically excellent images — my job is to look out for the subject itself and make sure I've focused properly. All in all, I suppose this lens won't always produce extraordinarily crisp and contrasty images that pop out of the screen (I've had a few "woah, that's shiny), but they won't be anything close to subpar either.reviewed December 31st, 2006 (purchased for $680)
Sure, the focus ring is a little narrow and a bit stiff, but it isn't sloppy or inaccurate. The zoom ring can feel sticky and imprecise if the torque is unbalanced or if one turns the ring slowly; turning it quickly and stopping at the desired focal length works better.
The focal range covers a very useful range, though for me lacking on the telephoto; for that I'd want something between 135mm and 300mm, but that can't be fit into a lens this portable. The Image Stabilizer is fantastic, but since I find myself shooting indoor performances for school, a 2.8 or larger would be good to have. So except for that venue, the f/4-5.6 isn't a hindrance. This lens' focus hardly hunts, even in said dark venue. I can carry this lens with me all day, every day. Finally, I don't think I'd give up the 55mm-85mm range to get the 17-55mm 2.8 IS, because of the bulk for perpetual carry, and the extra tele and magnification ratio for close-ups.
As is often said, one can't take a photograph with a lens one left at home. This lens is relatively compact and lightweight, and combines a very useful range with very good image quality and shot-saving IS.
8 out of 10 points and recommendedFairly lightweight, pretty fast AF in good light, sharp enough to ~250mmVery soft above 250mm (in certain conditions Ã¢â¬â it's not all bad up there)
Sure, it's an older, consumer lens, but if that's what you have then that's what you've got to use. Rather soft between 250-300mm, and CA is high around those ranges as well. AF can miss sometimes, and that's a huge range for the glass to cycle through when it doesn't catch. Manual focus is difficult due to the looseness of the ring.reviewed December 31st, 2006
All that said, the IS is useful (makes a loud *thunk* when activated, but that doesn't affect performance). Moreover, under 200mm, the image quality is really quite decent. The zoom ring sounds harsh (sounds like sliding a cardboard box over felt carpet) but is easily wieldable and not sticky. The front end extends significantly, but one doesn't notice at all when caught up in the action of the event. This lens is a splendid budget tool for outdoor sports, and can achieve high enough shutter speeds that the softness at 300mm is unnoticed if one catches a contorted player up close. However, I would advise against using it in any indoor situation without flash if there is to be any subject movement at all; still life could be fine, but even slow-moving novice ice-skaters will force the ISO up to 1600. Lastly, it's rather light and good for traveling.
10 out of 10 points and recommendedZoom range, aperture, build and image quality, weightFocus accuracy (unit specific, mine fixed by Sigma Service)
Extraordinarily sharp and contrasty when the focus is on. My particular unit front focuses by about an inch to two inches when shooting closer than 2-3 meters. However, the HSM allows for a quick touchup. This is fine when one has time to shoot, but not in close action with large apertures where the DOF really necessitates accurate placement of the focal plane, such as wedding receptions. Perhaps Sigma calibration will help, in which case I'll report new findings.reviewed May 18th, 2007 (purchased for $680)
A little CA in tricky situations.
I should note that though the amount of blur caused by misfocusing still produces better images than certain cheap lenses, it's frustrating because manually tweaking the focus shows what this glass is really capable of, even at 150mm.
Used on a Canon 350D and 400D. Setting AF to the back button rather than the shutter release can facilitate the manual tweaking process when taking many pictures at the same subject distance.
eta: I sent the lens in to Sigma for service. Focus is now spot-on, making f/2.8 a real pleasure to use with this tool. Also works splendidly on a Canon 30D.
10 out of 10 points and recommendedAll manner of optical criterea (see cons); balance on xxD, even xxxD; aperture combined with ISMore prone to flare than Ls, but really not that noticable except shooting into the sun.
I essentially agree with tukaway, but wanted to add a few things.reviewed September 1st, 2008 (purchased for $950)
Most importantly is that I haven't had any dust problems so far, despite using it every day in an outdoor, albeit fairly clean i.e. park-like environment for five months, interior construction sites, and several excursions in major cities.
Granted, the build quality isn't up to L levels, but as such it hasn't impeded my shooting style in both the slower landscape/architecture, or faster street/close action. The focus ring is noticeably smoother than the Canon 17-85mm's, but is finicky, sometimes feeling as well damped as an L's, and sometimes grainier.
The relatively large max. aperture combined with a 3-stop image stabilizer is simply super. Handheld nightscapes in cities are no problem. But if this didn't have IS, like Nikon's 17-55mm, I would pass up this lens for the price.