A versatile wide-angle prime, this 18mm lens is designed specifically for full-frame E-mount mirrorless digital cameras, however can also be used on APS-C models where it will provide a 27mm equivalent focal length.Maximum f/2.8 aperture is suitable for working in difficult and low-light conditions.Distagon optical concept incorporates 11 elements within 10 groups, and also employs a floating elements design to maintain consistent image quality throughout the focusing range.Two aspherical elements, five elements made from special glass, and a pair of aspherical elements also made from special glass are featured, and all contribute to significantly reducing chromatic and spherical aberrations for improved clarity, sharpness, and resolution.Zeiss T* anti-reflective coatings have been applied to each lens surface to help minimize reflections in order to provide greater image clarity, contrast, and color fidelity.Integrated OLED display on the top of the lens shows the distance of the focal plane from the camera as well as the depth of field range for quickly recognizing the parameters of focus in use, even when working in low-light conditions.Linear motors benefit the autofocus performance of the lens and provide smooth, fast, and quiet operation. For manual focusing, a rubberized ring offers greater tactile control for precise placement of focus.