While it's not the sharpest lens in the bag, the Sigma 12-24mm showed fairly decent results for sharpness. For optimal performance the lens must be stopped-down significant, to at least ƒ/8 or ƒ/11. CA is well-controlled and distortion is remarkably so.

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 do not plan to create a full Sigma 12-24mm f/4.5-5.6 EX DG HSM Lens review - hopefully the standardized results for this lens will be helpful to you.

The Sigma AF 12-24mm f/4.5-5.6 HSM DG II is the only "one size fits all" (formats) ultra-wide zoom lens on the market. It can give you decent results and truly extreme views on full format DSLRs and it is very good along across the more "conventional" zoom range on APS-C DSLRs.

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.

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

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

Sigma Wide Zoom Lens . If you want a panorama of a landscape then you should try this lens. Described as 12 - 24mm f5-5.6 EX DG Aspherical HSM Technical details first. To fit Sigma, Canon and Nikon (D ) Lens construction Groups/elements 12 / 16 Angle of view (degrees) 122.0 - 84.1 Diaphragm blades 6...

Excellent field of view

none that I have found in months of use