A favored and versatile focal length coupled with an optically refined design, the Leica APO-Summicron-SL 35mm f/2 ASPH. is a general wide-angle prime designed for full-frame L-mount mirrorless cameras. The bright f/2 maximum aperture strikes a balance between speed and overall weight and size, offering a portable form factor along with the ability to excel in available light conditions. The apochromatic optical design uses anomalous partial dispersion glass to suppress colour fringing and chromatic aberrations for high clarity and colour accuracy, and five spherical elements are also featured to reduce spherical aberrations for improved sharpness. Multi-layer coatings have also been applied to limit flare and ghosting for increased contrast when working in strong lighting conditions. Complementing the optics is a Dual Syncro Drive stepping motor, which delivers fast and quiet autofocus performance to suit both stills and video applications. Additionally, an AquaDura coating has been applied to the exposed elements and seals have been incorporated in the lens design to benefit working in harsh environmental conditions.