Digital-Images4u

This ultra wide angle zoom lens offers 122 degree super wide angle of view along the diagonal axis Sigma will always be guaranteed a place in the history books as pioneers of the wide-angle zoom lens. Our advanced super wide angle technology was developed far earlier than any of our competitors. Sigma designed and produced the first wide-angle zoom lens, the ''zoom gamma 21-35mm F3.5-4.2'', in 1979. The wide-angle zoom category didn't even exist before this date. The market comprised only standard and telephoto zoom lenses with most people believing that wide angle zooms were impossible to develop. However Sigma's advanced design and pioneering technology went on to prove them wrong and strongly influence subsequent product development. Optimized for Digital SLR Cameras 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. HSM (Hyper Sonic Motor) 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, built-in petal shaped lens hood. Minimum focusing distance of 28cm/11in. at all focal lengths 12-24mm F4.5-5.6 EX DG lens offers a minimum focusing distance of 28cm/11in. at all focal lengths. The super-wide angle's useful range of view offers the photographer greater freedom of expression. Fixed Petal-type hood is incorporated This lens is equipped with a fixed Petal-type hood to obtain a superior extraneous light-blocking effect.