An impressively wide and fast lens, the Summilux-M 21mm f/1.4 ASPH. from Leica is a versatile M-mount prime delivering exceptional image quality. The super wide-angle focal length is complemented by the use of five anomalous partial dispersion and a pair of aspherical elements to suppress chromatic and spherical aberrations in order to deliver a high degree of sharpness and clarity with well-controlled vignetting and distortion. The optical design also incorporates a floating elements system to provide consistent image quality throughout the focusing range.