Sigma 500mm f/4 DG OS HSM Sports Overview Loaded with almost every piece of technology in Sigma's Global Vision arsenal, the 500mm f/4 DG OS HSM Lens takes its spot as the flagship in the speedy Sports line. Available here with a Canon EF mount, this super telephoto lens lets you capture distant subjects, and with a speedy Hyper Sonic AF motor users will be able to easily track fast action. A relatively fast maximum aperture of f/4 furthers your imaging potential with excellent illumination for a lens of this class. One SLD and two FLD elements help ensure outstanding optical performance by minimizing aberrations and distortion while a Super Multi-Layer coating combats flare and ghosting. Also, this lens is equipped with an Optical Stabilizer system that compensates for up to 4 stops of shutter speed. This large lens is designed to be used in some of the most trying conditions and is made from a durable and lightweight magnesium alloy. It is protected from dust and water and uses a brass bayonet mount. Filter users will appreciate a 46mm drop-in filter system while a rotating tripod collar is available for using the lens on a tripod or monopod. Additionally, the 500mm lens is fully compatible with Sigma's Global Vision teleconverter for getting an extended reach.