Developed for the demands of digital photographers, the EF 16-35mm f/2.8L USM wideangle improves on its predecessor with a shorter beginning focal length, better close focusing capability & improved peripheral brightness in the image corners. All of the "L" lenses deliver optical performance equal to similiar fixed focal lengths lenses, and the USM lenses do this with silent, high-speed focusing. Distortions and aberrations are remarkably small for a lens of such amazing capabilities.