The Sigma 18-35mm f/1.8 DC HSM | Art is the first wide-angle to standard zoom lens to achieve a large aperture of 1.8. It is designed specifically for APS-C sized sensorsand incorporates a wide glass molded aspherical lens with Special Low Dispersion (SLD) glass to compensate for aberrations and curvature at the widest angle. This lens has an internal focusing and zooming feature that allows for more usability and functionality and makes it ideal for landscape photography, portrait photography, still life photography, snap shots, casual photography, and close-ups.