Sigma 10-20mm f/4-5.6 EX DC HSM

Astounding lens in every way, both price and quality. Even if the "big name" lenses bring better quality (how can they?), it's not an excuse for a price that's over double of this lens. And though inexpensive in terms of ultra wide angle lenses, the quality of the images is as good as it gets---to see the lens quality be bad I'd need 10 to 20 more years of experience , and with that I could then also circumvent the possible caveats of this thing..

I didn't dare buying a wide angle lens before I was more or less sure I could get something for the price, but having bought this Sigma lens now I sort of hate myself not buying it earlier already!

Very good image quality. Aberration is visible as with any wide lens, but in practical images (i.e. in images not shot at lab with intentions to find aberrations) not easily seen unless looked for. Build is firm, better than most Canon lenses I see. Comes with a hood. Full-time manual focus in addition to AF, which is a big plus.

Nothing at this price; if it cost more than twice it's price, I'd probably say something about aberrations in lab shoots or about my flash not being able to cover the area under 14mm without the extra plate, but then again, those are usually minor problems. And since it's this cheap, I don't cry---aberrations just teach to think better, shoot better.

Nothing as wide as this, as there's not much available.

Excellent. (plus I got this lens mailed to me in one day)

Great lens!

Sharp, excellent build quality, reasonable filter size (77mm).

Can't use flash in camera (Pentax *ist DL).

Using this lens really widens the view for any frustrated APS-C D-SLR user.The width available with this lens is incredible and opens up a whole new world of wide angle photography.
Quality has traditionally been an issue when deciding on OEM lenses or third party but this is one of the better ones that Sigma has produced with good all round performance and relatively low edge distortion for such a wide field of view.
The lens has a good quality, solid feel about it and focuses smoothly on my D200.
A great addition for any APS-C Dslr user.....Must Have!.

Extreme wide angle FOV.
Good if not excellent build quality.
Compact.
Low edge distortion(relative to angle of view).
Low lineal distortion(less than I expected).
Smooth auto focussing.
Cheap price.

Can't really fault this one given it's low cost and good performance.

Nikon 12-24mm Nikkor.
Nikon 18-35mm Nikkor.

None needed-loaner lense.

Dollar for dollar this ultra-wide performs. Weight is not an issue, size is super and it easily replaces one of my Zuiko Lenses in my camera bag. With the 10 - 20mm Zoom I have full coverage with my lens sets to 400mm and all easy to pack up and carry.

$499 is a great price for this lens. Little flare issues, sharp, (obviously not as fast as some, but for the money spent - no issue here). Good thing for this user is that it shares my 77mm filters, used on another lens I carry.

Smooth manual focus, and excellent auto-focus. Zoom is smooth and lens performs well on the Olympus E-3. I have read that some users of ultra-wides experience focus ease - I did not experience anything out of the ordinary in that regard.

Can't say enough good things about B&H. They had it in stock and shipped to me in less than a week from order date.

Used with care and conscious of composition issues with a ultra-wide, the focus and distortion control are incredibly easy to deal with. I was able to get very sharp images in medium to low light hand-held. With a tripod - there is nothing this lens can't do, that the more expensive lenses do.

For a person working on a budget, this lens is the way to go. Thanks to Sigma for working out the bugs on this 4/3rds aspect super wide angle lens.

Putting economics before pride - I am very happy with this lens and recommend it as an alternative to more costly ultra-wides. Money well spent!

HSM Focusing is quiet and blistering fast.
Manual focus is easy to use. User can be confident of a sharp image.
Composition and distortion is easily achieved in camera position to subject. Not a difficult feat.
Personal like: 77mm lens works with my expensive filters. No vignetting noticed in test shots.

None yet. This lens is built to perform, and as a air traveler, my back pack will provide good protection for this lens, kept in my camera bag, inside my roller board backpack. Nothing weak about this economical performer.

I have 2 other SIGMA lenses and they perform well. With all the money I have saved using SIGMA, I can afford to FLY and TRAVEL more often! :-)

Hopefully I will never have to go here. I have used SIGMA products for years, and with good care and not chancing a lens to adverse operating environments - I will hopefully never have to deal with customer service.

Must give B&H one more kudo. These folks are GREAT and the PRINTED CATALOG they sent to my home is a staple "Counter Book" in my kitchen. Everything to make a photographer to drool over. Their approach to business is to keep you as a customer. I am glad that I am and I will go back in the future. Give them a try!

I've been in photography since 1958 and have used many lenses and cameras during that time. Wide angle lenses have always been part of my photography.
My first Sigma lens was a 24mm f2.8 MF back in 1976 used on a Nikkormat FT2.
The widest lens I've used (until this Sigma) was an 18mm Nikkor f3.5 (which at $760.00 18 years ago was very costly!). Any shorter lens was out of the question due to the price.
Sigma has changed all that with this lens. The results I get doing interior photography in homes, businesses and industrial settings with a D70 using RAW files, rival the results I used to get with the 18mm Nikkor and my 28mm PC Nikkor lens on film. Straight lines stay straight and any perspective corrections (minor with good shooting practices) can easily be corrected in Photoshop Elements 3, 4 or 5.
The color is consistant with past results on film (and shooting digital means that color can be tweaked to choice quite easily!). The lens has good build quality, smooth manual focusing and quick quiet electronic (HSM) focusing. It's fun to use and stays on one D70 body while the other D70 has the Nikkor 18-70 f3.5-4.5 or the Sigma 24-70 f2.8 DG lens attached (I always keep an 80-200 f2.8 Nikkor nearby to fill out my go-anywhere kit). This lens is worth the $500.00.

Good color, accuate focusing and just the right size on the D70.
The light fall-off in the corners (have you seen some of the $1,800.00 primes?) is nothing to be concerned about since the main subject is never in the corners!
Allows a range of creative results at extreme close-up that other wide angles cannot duplicate. Flare control is good (and looks good when you use it for effect!). The price is right. It's a good lens to learn wide angle photography with.

I use a glass lens cap and the hood all the time.
I always replace the Sigma front and rear caps with Nikon caps.
There are no other caveats.

Nikkors: 18mm f3.5 MF, AF18-35mm f3.5-4.5, AF18-70mm f3.5-4.5,
MF 25-50mm f4, 28mm f3.5 PC, 24mm f2.8C
Sigma: MF24mm f2.8, AF24-70 f2.8 DG

None