Super telephoto lens series canon l lens mount canon ef lens speed 56 focal length 400 mm suitable for sensor types aps c full frame construction prime lens area of use animal photography focus manual focus internal focus auto focus af motor ultrasonic motor usm closest focusing distance 350 cm lens construction groupselements 67 number of aperture blades 8 minimum aperture 32 max aperture 56 filter thread 77 mm length 256 mm lens dia