This 24-70mm f/2.8 DG OS HSM Lens from Sigma for use with Nikon F-mount cameras is a high-quality wide-angle to portrait suitable lens. Being part of the highly classified Art lenses from Sigma, this lens' optical design is also sophisticated with such features as three SLD elements and four aspherical elements to reduce chromatic and spherical aberrations, as well as color fringing, distortions, and other anomalies for greater clarity and sharpness.