This large aperture telephoto zoom lens incorporates Sigma’s original OS (Optical Stabilizer) function which offers the use of shutter speeds approximately 4 stops slower than would otherwise be possible. This enables hand held tele-photography easily. Six SLD glass elements provide excellent correction for color aberration. The Super Multi-Layer Coating reduces flare and ghosting and provides high image quality throughout the entire zoom range. HSM ensures fast and quiet auto-focusing as well as full-time manual focusing capability. This lens incorporates an inner focusing and inner zooming system. The overall length of the lens does not change during focusing and zooming, ensuring convenient handling. This lens has a minimum focusing distance of 80cm and maximum magnification of 1:6.3. The rounded 9 blade diaphragm creates an attractive blur to the out of focus areas of the image.