Sigma 17-50mm f/2.8 EX DC OS HSM Lens for Canon Digital SLR CA17-50F2.8

Sigma's new 17-50mm F2.8 EX DC OS HSM large-aperture standard Zoom Lens covers a focal length from 17mm wide angle and offers a large aperture of F2.8 throughout the entire zoom range, making it ideal for many types of photography especially portraiture and landscapes. The OS, Sigma's anti shake feature offers the use of shutter speeds approximately 4 stops slower than would otherwise be possible. HSM provides fast and quiet AF. Sigma's own FLD glass elements, which have performance equal to fluorite along with two glass mold and one hybrid aspherical lens, provide excellent correction for all types of aberrations. The Super Multi-Layer coating reduces flare and ghosting. This lens boasts superior peripheral Brightness and provides sharp, high contrast images even at the maximum apertures. With a minimum focusing distance of 11 inches throughout the entire zoom range and a magnification ratio of 1:5. When you need to stand ready for any photo opportunity you need a fast aperture so you can shoot in low existing light or at maximum range with a flash. This Sigma lens is perfect. With its compact size and lightweight, it's a necessary addition to your camera bag.
Features

For use with smaller chip APS-c or 4/3 Digital cameras only

Offers Sigma's OS System (Optical Stabilization) allowing handheld photography even in low-light situation

HSM (Hyper-Sonic Motor) ensures a quiet & high-speed Auto focus

FLD glass elements with performance equal to fluorite glass for compensate for Color aberration

Ultra compact with overall length of just 3.6"
Specifications

Lens Construction: 17 Elements in 13 Groups

Angle of View: 72.4-27.9

Number of Diaphragm Blades: 7

Miminum Aperture: f22

Minimum Focusing Distance: 28 cm / 11 in

Filter Size (mm): 77

Maximum Magnifications: 1:5

Dimensions (Diameter x Length): 83.5 x 91.8 mm / 3.3 x 3.6 in.