Overview A unique and indispensable addition to Canon's series of EF lenses, the new EF 40mm f/2.8 STM offers an ultra-slim and lightweight design. Incredibly compact in size, the EF 40mm f/2.8 STM delivers high image quality from the center to the periphery thanks to its advanced lens configuration including an aspherical element, a bright 2.8 aperture, and optimized coatings that minimize ghosting and flare while providing exceptional color balance. The EF 40mm f/2.8 STM's unobtrusive design helps the photographer avoid overwhelming their subjects with a large lens and to remain discreet in sensitive shooting situations with no compromise in performance. Its diminutive design is complemented by features such as a newly developed stepping motor for smooth and quiet continuous AF while capturing video with the Canon EOS Rebel T4i DSLR, a circular aperture (7 blades) for beautiful soft-focus backgrounds, and a short minimum focusing distance of only 0.98 ft./0.30 m.