Customer Reviews
I am Impressed 
2008-08-05
I have only just received this lens so I will be giving you my first impressions. I will follow up in a couple of weeks with an in depth review.
First impression is BIG. The lens is big, physically, and it's a WIDE view after using my Canon 18-55mm. It feels solid, well built with everything moving very smoothly and no noise. It locks on to my Canon 300D and 400D XTi solidly with no slop and responds to all commands, AF, Av, Tv, etc.
I have taken half a dozen shots and they have all been clear and sharp without enlarging or in depth investigation. Distortion is typical of what you would expect in this focal length, exaggerating all the mid range distortions. I did manage to get some very respectable non-distorted images by carefully controlling the angles of the POV.
The last observation is that it looks good. I mean it's dressed up a little with the gold band and ribbing.
I am very happy with this lens so far. I will update this review after I play with it a little more in depth.
Solid, but Fuzzy 
2008-08-04
I have taken nearly one thousand pictures with this camera, anything from architecture to nature. While my initial assessment of the camera was good, after having it for some time, I feel that the fuzziness of the pictures is unacceptable. I guess I felt as though it was my initial settings, or maybe becuase of the wide angle of the lens this was something that was par for the course. I have since read about softness on right or left side with this leans, but my experience is clarity is no good accross the entire frame, in EVERY situation. I will either send back for repair or get rid of it for the cannon 10-22 lens.
Better sharpness, brightness and color saturation than Canon's 10-22 2008-07-28
I just did some test shots comparing the Sigma 10-20mm and the Canon 10-22mm. The Sigma beat the Canon hands down on sharpness, brightness and color saturation without question. I've owned the Canon 10-22mm for almost a year and have never been satisfied with the softness of the images it produces. I've even sent it to the factory 3 times for adjustment. The tests I did today show the Sigma to be surprisingly the better lens hands down. It may be that I purchased a bad Canon lens, but after 3 trips to the factory for adjustment, I would think it would have been spotted. I'm constantly being told by reps how good the Canon 10-22mm is as it has the super UD glass and is supposed to be similar to L series quality. I've never seen this on my 40D and I'm now ecstatic to have found the Sigma to replace it. This is a great lens for a very nice price.
bad......bad sharpness....... 
2008-06-21
I used this lens for 1 week and took over a 200 photos in various shutter speed/aperture combinations; all of them turned out so-so to no good. The center sharpness is ok, but the sharpness and distortion of the image becomes unacceptable, starting about half-way to the image edge.
I don't believe I received a bad copy of this lens as a previous reviewer had as I didn't find one side of the image to be better or worse than the other and the autofocus seemed to be on target.
SAVE SOME CASH 
2008-06-18
SAVE A FEW HUNDRED DOLLARS, GET THIS INSTEAD OF THE 10-22 BY CANON, CANON IS THE BETTER OF THE TWO, BUT, NOT FOR THE MONEY, IF YOU HAVE LENS FEVER! THANKS, SIGMA.
Great wide angle! 2008-06-12
10-20mm F4-5.6 EX DC HSM lens allows enjoyment of super wide-angle photography and it is a very powerful tool for indoor shooting and landscape photography with APS-C size image sensors of digital SLR cameras.Wide angle of view (102.4? at 10mm and 63.8? at 20mm) offers the photographer greater freedom of expression. Three SLD glass elements are employed for effective compensation of color aberration, which is a common problem with super-wide angle lenses. One piece of glass mold and two hybrid aspherical lenses, offer excellent correction for distortion, as well as all types of aberration.This lens is equipped with an inner focusing system, and the models which are equipped with HSM system provide quiet, high speed autofocus shooting and also offer full time manual focusing. It has a minimum focusing distance of 24cm (9.4") at all focal lengths. The non-rotating lens barrel perfectly suits the petal shaped lens hood. A circular polarizing filter can also be used conveniently.
fantastic 2008-06-02
This is my first "real lens". the Sigma EX line is a good place to start getting into quality glass. I was looking for something of a fisheye (maybe not that extreme) but definitely something wiiiiide.
This fits the bill very well. It is not the most extreme angle but it really captures depth/space in the frame and creates an interesting look. You'll learn to be aware of your entire environment as the wide angle can capture things on the extreme periphery. It makes scenes more lively, i had my sister shoot with this lens at a wedding reception with some very entertaining results.
Only concern is that this is an f4 lens compared to Canon's L series wide lenses that hover around f2.8. But then you'll spend over twice as much!
Nice price for a great lens 2008-05-28
Sigma continues to impress me. My one pricey Canon-brand lens (28-70 f/2.8 L) has color-fringe problems, and my two Sigmas (this one and the very sweet APO 70-200 f/2.8 EX DG HSM) are dead-on correct and free of chromatic aberration. My chief complaints about this lens are fairly irrelevant since they center around its inherent design:
1) variable aperture (makes you have to change your flash settings if you shoot manual)
2) it's not a f/2.8 lens
I was aware of these design specifications (not issues or surprises) before buying and am pleased with it despite them. That's the tradeoff you get for a great price.
It's nice to have a true wide-angle lens back in my arsenal, since the 28-70 combines with my 1.6x sensor size factor to become a 45-112, hardly wide.
To anyone considering buying the lens, just be aware that it's not for full-frame cameras. If you don't know what this means, or aren't sure what yours is, read the manual.
The field of view is an immense 102° side-to-side, and it focuses down to about 6" from the subject at 10mm.
Overall, a great value. 2008-05-27
I bought this instead of the Canon 10-22, and never looked back. Reviews seemed to indicate they were fairly comparable, with no clear "winner" in Amazon user reviews or in the trades, but I was on a strict budget and had 2 lenses to buy: this was the one that went cheap.
In use it is very good. When wide open at the 10mm end there's vignetting and some chromatic aberration is visible (the dreaded "purple fringe" variety) at wide apertures. Start tightening up the view, though, and it gets much better pretty quick, say by about 12mm@f/8.
At the 20MM end it is sharp, clean, and lovely. I've done portraits with it - pretty pleased with the outcomes.
But what I bought it for was that big, nasty 10mm wide angle barrel distortion thing, and shooting hand held outdoors in low light or straight into the sunset at 10mm with the aperture at f/22 or so it is just great.
I only saved a few hundred bucks, but no buyer's remorse here. None of the complaints about short focusing soft spots or bad workmanship for me.
Highly recommended.
After 3 weeks I ended up returning mine 2008-05-22
I used this lens for 3 weeks and took over a hundred photos in various shutter speed/aperture combinations; all of them turned out so-so to no good. The center sharpness is ok, but the sharpness and distortion of the image becomes unacceptable, starting about half-way to the image edge.
I don't believe I received a bad copy of this lens as a previous reviewer had as I didn't find one side of the image to be better or worse than the other and the autofocus seemed to be on target.
When purchasing a wide angle lens, for the most part, it's to capture more of a given scene. This additional part of the scene is of course found around the edges of the frame. Therefore, I sent this lens back and am in search of a better one.
Note, the build quality seemed solid and the autofocus was snappy. If only the overall sharpness were better I would have kept it.
