The Sigma 180mm f/2.8 APO Macro EX DG OS HSM Lens (for Sigma) is a high-speed macro lens offering a magnification ratio of 1:1 and a focal length of 180mm. This lens is compatible with the Sigma SA mount for use on APS-C DSLRs.,,This lens incorporates 3 FLD glass elements for color aberration corrections, as well as a floating inner focusing system to reduce other aberrations such as field curvature and distortion, resulting in accurate scene rendition from 1:1 magnification to infinity. A Super Multi-Layer coating helps to eliminate ghosting and flare as well as produce images with more contrast and sharpness. The rounded 9 blade diaphragm also provides an appealing bokeh, especially when photographing at the maximum aperture or at 1:1 magnification.,,The integrated OS (Optical Stabilizer) system permits users to photograph handheld with shutter speeds up to 4 stops lower than usually possible. An HSM (Hyper Sonic Motor) is also incorporated into the design, ensuring quiet and quick auto focusing and manual focus capabilities.,,,High-speed f/2.8 180mm macro lens provides 1:1 magnification ratio.,FLD glass elements and a floating inner focusing system help to correct for color aberration, field curvature, and image distortion.,Multi-layer coating reduces ghosting and flare and provides greater contrast and color fidelity.,Rounded 9 blade diaphragm produces an attractive out of focus quality.,Integrated Optical Stabilizer system permits users to photograph handheld with shutter speeds up to 4 stops lower than usually possible.,A Hyper Sonic Motor is incorporated into the lens design, ensuring quiet and quick auto focusing and manual focus capabilities.