Sigma unleashes fast 50

A fast--F/1.4--50mm lens for some digital cameras was announced this week by Sigma Corporation. According to the company, the lens has "superior peripheral brightness even at the maximum aperture and corrects a possible sagittal coma flare." On DSLRs with APS-C sensors, Sigma says, the glass effectively becomes an 80mm medium telephoto lens. It adds that a super multi-layer lens coating reduces flare and ghosting, and that the unit's optical design and molded glass aspherical lens elements provide excellent correction for all types of aberrations. Minimum focusing range for the lens is 17.7 inches. The  unit incorporates Hyper Sonic Motor (HSM) technology for fast and quiet auto focusing, as well as a full-time manual override. The model  has mounts for Sigma, Canon, Nikon, Pentax and Sony digital cameras, but Pentax and Sony do not support HSM so the glass won't auto focus with those brands. Availability and pricing were not released by Sigma at the time of the announcement.