A 12mm rectilinear lens with its 122° angle of view is a specialty item for a full frame camera. It is a very difficult focal length to compute and manufacture, which is why there are only two of them available. With a lens like this there is bound to be substantial vignetting, and rectilinear distortion. It comes with the territory. Nonetheless, it is one of those lenses where, if you need it, you need it, and will be willing to put up with the necessary post-processing tweaking it will take to massage the final image into submission. Fortunately, Adobe Camera Raw has a profile for the Sigma 12-24mm zoom making correction a simple matter of checking a box.
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| The Sigma 12-24mm zoom lens on a Nikon D800 |
The Sigma 12-24mm lens has a variable aperture of f/4.5-5.6 -- not exactly speedy, but then most applications of such a short focal length would typically require stopping down even more to a working aperture of f/8-16.
I performed most of my tests at the widest focal lengths, figuring that anyone acquiring this lens is doing so primarily for the 12mm length, and, if anyone wanted a 24mm, there are much better options available. Personally, I would have preferred for Sigma to simply have made a 12mm prime instead. It would have been easier to compute and less of the optical compromise necessary in manufacturing a zoom lens.
It is not a huge lens, medewinaring 3.3" x 4.7" (83.82 x 119.38 mm), and weighs 23.63 oz (670 g). The scalloped lens shade is built into the lens. The lens shade is in two parts and can double to convert the lens into a circular, pseudo-fisheye. Its 12-24mm zoom range covers an impressive viewing range of 122°- 84°
This Sigma 12-24mm lens is priced at $949, and is an update -- and significant improvement -- over a prior model.
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| The extreme wide angle reaches high into the deeper blue area of the sky for more dramatic effects with clouds. |
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| A 12mm panoramic vista of lower Manhattan with the Manhattan and Brooklyn bridges. |
In general, Sigma has done a decent job of controlling chromatic aberration in the lens. I did some tests where I know I would be pushing the limits, such as in the photo below. Vignetting and rectilinear distortion are quite apparent, especially at the widest focal lengths, but all of this is something I expect when pushing the limits of lens technology with such a wide angle.
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| This scene was taken to illustrate the chromatic aberration of the lens. Download a high res, side-by-side comparison of the image, both with and without correction using Adobe Camera RAW. Download by clicking here. The chromatic aberration is most apparent in the building in the upper left corner of the frame. Corner softness is also evident in this sample, but the high resolution characteristics of the lens in the main areas is a big plus. |
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| Since Adobe Camera RAW already has the data for the Sigma 12-24mm lens, simply checking the enabling boxes for lens corrections corrects the lens flaws of vignetting, distortion, and chromatic aberration. |
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| This is the ancestral home of Fox Talbot, the British inventor of the negative-positive photographic process. He could not have even imagined that his invention would eventually lead to a hand-held digital image such as this taken with a Nikon D800 and the Sigma 12-24mm zoom set to 16mm and f/8. |
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| Stonehenge with foreground detail. |
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| Architectural shots, such as this interior of the Fox Talbot ancestral home, is a natural use of an extreme wide angle. |
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| Bryce Canyon taken at 14mm and f/10. |
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| New York's Times Square at a 17mm setting. |
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| The unusual perspective of integrating foreground detail with a background scene is what this lens is all about. |
CONCLUSION:
I suspected coming into this review that this would be a lens with problems, but, as I mentioned earlier, if you need the drama it can deliver, you will have to pay the piper with some post-processing work. As it turned out, the corrections are simple and fully justified adding this lens to my personal arsenal of optics for my Nikon system. The only other 12mm lens made for a full frame camera is the Voigtlander Heliar 12mm f/5/6. The only digital camera where it can be used is on a Leica M series, and it requires considerable post-processing correction to beat its images into submission.
My review of that lens can be read here.
Bottom line is, as 12mm is a very rare and specialized focal length, I would rather have the lens with the distortions than not have the lens at all. This is particularly the case when most of the problems are so easily corrected in post-processing through Adobe Camera Raw. I chose the photo samples above to illustrate where and why a lens with such an extreme wide angle comes into play.
The Sigma 12-24mm f/4.5-5.6 EX DG ASP HSM II lens comes in mounts for Nikon, Canon, Sony, and Sigma. It can also be used on APS-C sensors where it becomes a 18-36mm short zoom and eliminates much of the distortion because of cropping due to the smaller-sized sensor.
If you are planning on purchasing this lens, you can help support this site at no extra cost to you by purchasing from one of our affiliate sellers listed below -- and thanks for your support.
The Sigma 12-24mm f/4.5-5.6 EX DG lens for Nikon is available at: BH-Photo Amazon The Sigma 12-24mm f/4.5-5.6 EX DG lens for Canon is available at: BH-Photo Amazon The Sigma 12-24mm f/4.5-5.6 EX DG lens for Sony is available at: BH-Photo Amazon The Sigma 12-24mm f/4.5-5.6 EX DG lens for Sigma is available at: BH-Photo
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