Sigma 50mm f/1.4 DG HSM ArtFast and versatile, the 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