Sigma APO 17-50mm F2.8 EX DC OS HSM

Sigma APO 17-50mm F2.8 EX DC OS HSM

The Sigma APO 17-50mm F2.8 EX DC OS HSM is a lens with a focal length of 17-50mm, a maximum aperture of f/2.8 and minimum aperture f/22. It is constructed in 13 groups with 17 elements (two of which are FLD elements) and has an angle of view of 72.4°-27.9°. Its closest focus distance is 28cm / 11in. The lens also supports a maximum reproduction ratio of 1:5, and has 7 rounded aperture blades. Its filter attachment size is 77 mm, and the unit features a HSM autofocus motor. Measuring 83.5mm x 91.8.8mm (3.3in × 3.6in), the Sigma APO 17-50mm F2.8 EX DC OS HSM comes with a case and a LH825-03 petal-type hood and is compatible with Sigma, Sony, Nikon, Pentax, and Canon cameras.

Features

The Sigma 17-50mm F2.8 EX DC OS HSM is a lens with a large aperture range designed for digital SLR cameras and incorporates Sigma’s OS function. It covers a focal length from 17mm wide angle with F2.8 aperture throughout the entire zoom range, an OS (Optical Stabilizer) function that allows users to utilize shutter speeds approximately 4 stops slower than conventional cameras. This allows users to utilize the lens (on Sony and Pentax SLRs) even if the camera body is equipped with an image sensor shift anti-shake system. Other features on the lens include two FLD (“F” Low Dispersion) glass elements, two glass mold and one hybrid aspherical lens, which corrects almost all type of aberrations; Super Multi-Layer Coating which reduces flare and ghost; HSM (Hyper Sonic Motor) for quick and quiet autofocus function; a minimum focusing distance of 28cm (11”) throughout the entire zoom range and a maximum magnification ratio of 1:5; 7 rounded blade diaphragm that creates blur to the out of focus images and an inner focusing system which eliminates front lens rotation, making the lens suitable for use with petal-type lens hood and circular polarizing filters.