Product Includes EF Mount Lens An Aperture with Range of f/1.4-22 2 High Refraction Lens Elements Gaussian Optics eradicate Astigmatism Ultrasonic Autofocus Motor Infrared Index Manual Focus Override Minimum Focus Distance is 17.8inches Filter Thread Diameter is 58mm This EF 50mm f/1.4 USM Lens from Canon is a usual length lens featuring excellent quality and portability. Its f/1.4 maximum aperture makes it very useful in low light circumstances and capable to offer shallow depth of field focus. 2 high-refraction lens elements and latest Gaussian optics eradicate astigmatism and restrain astigmatic dissimilarity. Its ultrasonic autofocus motor (USM) allows speedy, smooth and noiseless autofocus action and permanent manual focus override enables for the accuracy of manual focus even in 1 Shot AF mode. Regular focal length 50mm lens is helpful in a large number of shooting conditions and perfect for day-to-day shooting. An f/1.4 utmost aperture gives apparent imaging in low light circumstances and low depth of field. Ultrasonic autofocus motor (USM) function is quick, smooth and almost silent.