Given the high bar set by Sigma's Art lenses, when I first heard about Sigma releasing this lens at a fairly affordable price I was extremely excited. Unfortunately though, the lens fell short in several aspects.

Landscape photographers looking for a wide-angle zoom lens with exceptional sharpness and performance from 12mm-16mm

Photographers looking for excellent performance across the entire focal range and photographers who prefer to shoot with a lighter kit

If you're into high quality glass, this is the kind of lens you can get lost in. Build quality is exceptional, performance is outstanding and…I'm getting ahead of myself, but you'll see the world in a whole new way when you use this lens.

This ultra-wide angle zoom lens from Sigma projects an image circle big enough for full frame digital/35mm and is still very wide on a cropped sensor. We take a look at how it performs.

Enormous field of view; Amazing control of distortions; Solid build quality with good protection of front element

Difficult to use front mounted filters (Though not impossible; Bulbous front element needs careful handling

Sigma 12-24mm f/4.5-5.6 EX DG HSM is one of about half a dozen ultra wide zoom lenses in Sigma's modern lens lineup. This is also one of the widest full-frame zoom lenses available on the market at this time (there are a couple of 'wider' APS-C type lenses offered by Canon, Tokina as well as Sigma...

I used to have a Sigma 15-30 before purchasing this lens, but I needed a larger angle coverage for some architectural pictures. This lens has no real distortion even at 12mm, and it's quite sharp if you use it at f.5,6 and over.

Very wide; Sharp over f.5,6; No distortion at all, a miracle

Needs to be stopped at f.8 and over for the best results

I have been using the generation one Sigma 12-24mm lens for wide landscapes and architectual shots for many years. The older lens was sharp in the center but soft at the edges and corners even when stopped down. The older lens was at its worst in the 12-15mm range, right where you needed it most.

I love this lens. I love it for promo photos, realestate , and even group photos. The only thing is I thought o was buying it in Canadian dollars and it ended up being U.S. prices. Ouch.

This is the ugliest imaginable lens... Sorry, but had to say that and get it off my chest. It just looks ghastly on my Nikon F5 and on the F100 too. Oh, well, now that I said it, I should add that it's a very good, reliable tool. Where does one get a wide-angle this wide Nowhere!

Speed, size and relatively discreet look (if it wasn't for that front element that's downright bulbous); Nice range of focal lengths

Maybe it's ugliness, along with that the front element is so weird looking and doesn't allow for filters of any type; Other than that, it's not a lens to use with flash 'cuz it vignettes like mad, especially at 12mm (and what's the fun of using a flash at 24mm with this lens None.

The Sigma 12-24mm F4 DG HSM Art is a new ultra-wide-angle zoom lens for full-frame and APS-C DSLR cameras. It offers the equivalent angle of view as an 18-36 mm lens on an APS-C system (depending on the crop factor).

I have owned this lens for about nine months now and have used it for both bird and mammal photography. I sold the Nikon 500mm f4 that I previously owned and after much research, eventually bought this one. I was much influenced by the superb testing of this lens by Canadian photographer Brad Hill.

Durable; Great Features; Great Picture Quality

Bulky; Heavy