Sigma 402965 f/16-16 Fixed Prime 16mm F1.4 Contemporary DC DN Lens for APS-C Mirrorless Cameras, Black The Contemporary line is part of Sigma Global Vision and is the perfect blend of image quality and compact size. The large aperture is great for lowlight and for creating depth of field. The optical design and stepping motor deliver smooth autofocus during video shooting. The lens design fully accommodates the Fast Hybrid AF of Sony E-mount cameras. Using face recognition AF results in consistent autofocusing on faces, even as the subjects move.