Average Reviews:
(More customer reviews)This is one of those "it's great BUT ..." reviews. If you don't care about the BUT part, feel free to add a star or two to my rating above.
First, a little background. I'm been an amateur photographer for almost 20 years, 80% of which was spent with SLRs. The 300D is my first digital SLR, but my 5th SLR and my 8th or 9th camera. Currently, I have 4 other lenses for my 300D, all holdovers from when I used my 35mm Canon Elan. The lenses are 50 1.8, 70-210 3.5-4.5, 28-105 3.5-4.5, and an 85 1.8.
Now to the Sigma. The user posts at dpreview's forum and elsewhere say it's pretty sharp IF you have a good sample. Those with bad samples report that this lens tends to front-focus, i.e. the actual focus point is closer than the desired focus point.
There wasn't really any lens in its price range that had the reported sharpness, and if I received a bad sample, I could have Sigma fix it, so why not, right? After all, owners of this lens reported it's sharper than the 300D kit lens, and while not quite as sharp as the Canon 17-85, it's less than 1/2 the price. (I bought mine before the Tamron 18-200 came out.)
When I received my 18-125, I was very happy with the build quality. It's a solid lens with smooth zooming action, and an included removable hood. The lens doesn't have Canon's nice USM's silent and ultra-quick focusing, and the Sigma's focus ring moved when focusing so watch where you leave your fingers, but otherwise no complaints.
But first, I had to make sure my sample didn't have the front-focusing issue. Since the DOF is narrower the closer the focus distance, I did all of my focus/DOF tests in the house and of nearby subjects outdoors. The focus point did seem closer than the desired subject but not closer enough to knock the subject outside the DOF so I accepted it. After all, the pictures were nice and sharp, even wide open, if you don't look too closely at the corners. So I was happy.
Then a month after I got the lens, my wife was in an "adventure race", where I shot hundreds of photos, all with this lens. Most were sharp but the ones of my wife far away (>50m) were noticeably less sharp. Looking more closely, I see that intermediate objects, e.g. the grass, in tele shots with the Sigma appear sharper than my wife. Rats! Does my sample have the front-focusing problem or did my 300D somehow focused on the closer objects?
ASAP after we got home, I took my Sigma out for some controlled tests, along with my 70-210 set at 125mm f5.6. Dozens and dozens of shots later, it's clear my Sigma has the front-focusing problem, but only noticeable with shots of subjects beyond ~50 meters, getting worse and worse with distance.
I pack it up and send it to Sigma's repair center, along with a note detailing the problem and how it only is apparent with tele shots of distant subjects. The lens comes back unrepaired with a sentence on the repair ticket saying the focus and DOF tests passed "ok", and a reference to the included CD. I load it and there are only 2 pics of 2 different test patterns, apparently indoors and only a few meters from the camera.
I call Sigma service, talked to a bunch of people, finally got routed to the head of the repair center, an apparently very busy man who implies it's my camera that's faulty and also that I didn't provide enough info to let them know the problem, i.e. I should have included sample pics. I mention I included a detailed explanation and his reply is, I kid you not, the techs are busy and don't have time to read people's letters!
Getting nowhere with them on the phone, I go home and shoot about 50 photos of a carefully selected scene with the Sigma and my Canon lens above, burned them all to a CD, write a more detailed letter, and send everything to Sigma.
2 weeks later, the lens comes back. Unrepaired. Again. The note says "infinity" focus and DOF tests passed "ok" and to see the pics on the included CD. I look at the 6 photos on the CD - 3 at 18mm and 3 at 125mm - and, unbelievably, the subject was a Sigma sign mere meters from the photographer, with distant trees in the background out of focus, of course.
Clearly we have a disagreement on what "infinity" or even "distant" means.
I will send the lens in a 3rd time but this experience has been so horribly frustrating, I know I will never buy another Sigma lens again.
If you buy this lens, make sure to immediately test the lens with close AND distant subjects as above, and return it immediately to the retailer if you have a bad sample. Good luck!
Click Here to see more reviews about:
Sigma 18-125mm f/3.5-5.6 DC IF Aspherical Zoom Lens for Canon Digital SLR CamerasThis Sigma AF 18-125mm F3.5-5.6 DC zoom lens was exclusively designed for use with digital Single-Lens Reflex (SLR) cameras and has 6.9 times high magnification zoom ratio. Image circle is designed to match the size of the image sensor of digital SLR cameras. A Special Low Dispersion (SLD) and two pieces of aspherical glass elements produce high levels of optical performance through the entire zoom range. This has resulted in a compact, lightweight lens. This lens has a minimum focusing distance of 50cm (19.6in.) at all focal lengths and is equipped with an inner focusing system. Since the front of the lens does not rotate, aPetal Shaped Hoodand a circular polarizing filter can be easily attached and used. This lens is also equipped withZoom Lock Switchthat eliminatesZoom Creep.Specifications: Lens Construction: Groups: 14 Elements: 15 Angle of View (diagonal): 69.3deg. - 11.4deg. Minimum Aperture: 22 Minimum Focusing Distance: 50/19.7cm Magnifications (Macro): 1:5:3 Filter Size: 62 Dimensions (Diameter x Length): 2.7 x 3 in. Fully Extended Length: 129.5mm/5.1 in.
Click here for more information about Sigma 18-125mm f/3.5-5.6 DC IF Aspherical Zoom Lens for Canon Digital SLR Cameras
