Designed for use with Canon's RF mirrorless digital camera range, the Canon RF 400mm f2.8 L IS USM Lens is a super-telephoto lens that is capable of capturing professional, high-quality and beautiful images. Ideal for wildlife, sports and action photography, the lens is one of the lightest super-telephoto lenses available for a mirrorless camera set up and as a result, this lens is surprisingly portable. The optical structure is made up of 17 elements, in 13 groups and this includes the use of two Fluorite and one Super UD glass, as well as the use of ASC and Super Spectra lens coatings. This optical makeup is complemented by a powerful Dual power focus drive that offers impressively fast autofocus acquisition, where focus is maintained even when tracking fast-moving subjects. The lens is also afforded a wide, bright and fast maximum aperture of F2.8 which together with the AF system and image stabilisation system, results in excellent and reliable low-light performance.