The Sigma AF 24ndash70mm f2.8 DG OS HSM Art Lens is meant for both landscape and portrait photography. It can be fitted on Sigma cameras with an SA mount. The optical design of the lens includes 19 elements in 14 groups. Three SLD and four aspherical elements are also incorporated into the design of the lens to reduce chromatic and spherical aberrations. A super multi-layer coating reduces ghosting and enhances color vibrancy and accuracy. With the Hyper Sonic AF motor the lens facilitates a fast and noise-free autofocusing. Its nine-blade diaphragm ensures a smooth bokeh effect on images. The lens has an optical stabilizer that reduces camera shakes while shooting handheld. This lens has a composite-material body and brass-bayonet mount.