The Sigma 24mm F2 DG Contemporary Lens in Black for Sony E Mount is a full-frame compatible lens that offers new value to mirrorless systems. The combination of superb optical performance with a level of compactness that is perfectly suited to smaller and lighter modern mirrorless cameras will bring you new opportunities for a perfect shot. The Sigma 24mm F2 DG Contemporary boasts exceptional optical performance with ultra-high resolving power to match the latest high-resolution mirrorless cameras. The AF drive system incorporates a quiet, high-speed stepping motor, making it suitable for still images as well as video recording.New Standards of Optical Performance for the Contemporary LineThe Sigma 24mm F2 DG Contemporary combines the highest level of optical performance even at its maximum aperture of F2 and a well-balanced body. The lens uses two SLD glass elements and one FLD glass element to correct axial chromatic aberration, which is a particular concern with bright lenses. It also incorporates two high-precision glass-molded aspherical elements, made possible by the processing technology of Sigma's sole production facility in Aizu. This has enabled the total number of lens elements to be kept down and the size and weight of the lens to be reduced, while providing excellent correction of various aberrations. In anticipation of wide-angle lens applications, Sigma's optical designers have ensured the lens resolution is extremely high, and is uniform from the center to the periphery of the image. Sagittal coma flare is also well suppressed, giving the lens a high degree of rendering power that makes it ideal for night sky photography. The AF drive system incorporates a quiet, high-speed stepping motor. This allows photographers to capture every detail of the spacious 24mm scene with precise AF.Use of Multiple High-Precision Aspherical Glass Molded LensesThe surface of molds for glass molding, which is a process that forms optical components by pressing glass materials at high temperatures, requires ultra-high precision. Sigma uses high-precision molds whose surfaces are controlled with an accuracy of plus minus 5 nanometers (0.000005 mm) or smaller. High-precision aspherical glass molded lenses archive both good aberration correction and compact lens size.Exceptional I Series Build Quality with a Compact Form-FactorAll I series lenses have an all-metal construction. The precision-cut aluminum parts not only give the barrel a sleek, stylish finish, but provide superb durability that improves the quality of the entire product. Metal materials are also used in internal structures that slide with the operation ring for added robustness. These high-precision components crafted with Sigma's cutting-edge metalworking technology are also used in Sigma's Cine Lens line-up for professional cinematographers and provide a tactile, ergonomic feel that make the lens a pleasure to use. The cover ring between the focus ring and the aperture ring has hairline processing that is also used for the rear cylinder of the Art line. This covering functions as a finger hold when attaching or detaching the lens.Magnetic Metal Lens CapI series lenses are accompanied by a dedicated magnetic metal lens cap, in addition to a normal plastic cap. This dedicated metal cap clips to the front surface of the lens magnetically. It is no exaggeration to say that this meticulously crafted cap represents the finishing touch for the I series.