Fast and versatile, the Leica L-mount 50mm f/1.4 DG HSM from Sigma is a normal-length prime designed to achieve high optical performance through the incorporation of both three Special Low Dispersion glass elements and one molded glass aspherical element. These elements, coupled with an advanced optical design, work to minimize sagittal coma flare and chromatic aberrations in order to provide high image sharpness and clarity. The lens' large diameter and floating system also help to correct for vignetting to ensure maintained peripheral brightness. A Super Multi Coating has been applied to lens elements, too, to reduce flare and ghosting for higher contrast and color fidelity. Additionally, making it an ideal lens for portraiture, the bright f/1.4 maximum aperture pairs with a rounded nine-blade diaphragm to benefit selective focus and shallow depth of field imaging with smooth bokeh.
Complementing the imaging capabilities, the lens sports a Hyper Sonic Motor to produce quick, smooth, and quiet autofocus performance with full-time manual focus override. The physical design utilizes Thermally Stable Composite material for durability in a wide range of environments, and a brass bayonet mount also offers rigidity and mounting precision.