The Sigma 12-24mm F4 DG HSM | Art Lens for Nikon F-mount DSLRs is an ultra-wide-angle zoom lens that is perfect for ultra-high resolution, full frame cameras. It offers an optimal package of centre-to-edge image quality, minimized distortion, and minimum focusing distance. To achieve these qualities without compromise, SIGMA has leveraged its lens design expertise and all of its leading-edge technologies. Advanced materials such as low-dispersion glass play a crucial role, while SIGMAs advanced lens processing methods have made possible an aspherical lens of extremely large diameter. Outstanding image quality The new SIGMA 12-24mm F4 DG HSM | Art leverages SIGMAs accumulated expertise in the processing and manufacture of aspherical lenses and incorporates multiple aspherical lenses produced with precision glass molding. The lens also features lens elements made with FLD (F Low Dispersion) glass, which is equivalent to fluorite in performance, and an optimized power distribution. Together, these features help minimize distortion, transverse chromatic aberration, and coma flare. As a result, image quality is outstanding across the image, all the way to the edges. F/4 brightness throughout the zoom range With F/4 throughout the zoom range, this lens is one stop brighter than conventional lenses. Photographers can now use a higher shutter speed that will crisply capture leaves fluttering in the breeze and other quick-moving subjects. A constant aperture during zooming also makes this lens exceptionally easy to use. Newly designed HSM for nimble AF control The newly designed Hyper Sonic Motor (HSM) is large, offers 1.3 times the torque of its predecessor. Even at low speeds, it offers exceptionally stable performance. | Sigma Unisex 12-24mm f4 DG HSM Lens - Nikon F in Black | Size: 24mm