The Leica DG Summilux 15mm f/1.7 ASPH. is a fast, versatile wide-angle prime for Micro Four Thirds, giving a 30mm full-frame equivalent field of view for reportage, low-light and available-light work. Its bright f/1.7 maximum aperture (aperture range f/1.7 to f/16) benefits low-light conditions and gives greater control over depth of field for selective-focus techniques. Three aspherical elements control distortion and aberrations, and Nano Surface Coating reduces ghosting and flare. A stepping autofocus motor with internal focusing keeps focus fast and quiet, and a manual aperture ring gives direct control over exposure. A rounded 7-blade diaphragm shapes background blur on the Micro Four Thirds mount, making this a compact option for street, documentary and event work in mixed and low light.