Sigma 12-24mm f/4.5-5.6 EX DG Aspherical HSM
(From Sigma lens literature) This ultra wide angle zoom lens offers 122 degree super wide angle of view along the diagonal axis.
Four Special Low Dispersion (SLD) glass elements are provided for effective compensation of color aberration, which is a common problem with super-wide angle lenses. Two pieces of molded glass and three aspherical lenses, including two molded glass aspherical lens elements, offer excellent correction for linear distortion as well as all types of aberration. It is an ideal lens for Digital SLR Cameras as well as film SLR cameras.
The lens is equipped with Hyper Sonic Motor (HSM) for Sigma, Nikon, and Canon. It is easy to revert to Manual Focus by simply turning the focusing ring and overriding the AF. An inner focus system provides high performance and convenience. The non-rotating lens barrel perfectly suits the matched petal-shaped lens hood.
12-24mm ƒ/4.5-5.6 EX DG lens offers a minimum focusing distance of 28cm / 11 in. at all focal lengths. The super-wide angle is useful range of view offers the photographer greater freedom of expression.
This lens is equipped with a fixed petal-type hood to block extraneous light.