The Sigma 12-24mm F4 DG HSM Art is a premium full frame wide angle zoom designed to have minimal distortion in its wide angle imagery. Part of the Art line, the Sigma 12-24mm F4 DG HSM Art was created from decades of experience manufacturing wide-angle lenses. FLD glass elements, with performance equal to fluorite, provide for exceptional image quality while an updated Hyper Sonic Motor (HSM) uses 1.3X the torque for quick AF. A constant F4 aperture through the entire zoom range allows for greater ability in low light compared to previous models and the use of the largest aspherical element in the industry controls distortion, ghosting and flaring. An emphasis on edge to edge performance brings stunningly sharp and contrasty images to life. Ideal for many types of photography, the 12-24mm F4 Art is perfect for landscape photography, architecture photography, interior photography and much more.This wide-angle 12-24mm f/4 zoom lens is designed for full-frame format Nikon F-mount cameras and can also be used with APS-C models where it will provide a 18-36mm equivalent focal length.F low dispersion and aspherical elements, including an 80mm large-diameter molded glass aspherical element, have been incorporated within the lens design to correct for chromatic aberrations throughout the entire focusing range and help to ensure high image sharpness, clarity and contrast regardless of focus point or aperture setting - this optical design also helps to control distortion and limit vignetting.