Capture stunning close-up shots with the Sigma 105mm f1.4 DG HSM Art Lens. This lens is compatible with Sigma SA-mount cameras and features an optical design of 17 elements in 12 groups. The three FLD and two SLD elements along with a single aspherical element offer clarity and color neutrality by combating various distortions. You get clear results in bright conditions thanks to the Super Multi-Layer Coating. This Sigma telephoto lens comes with a Hyper Sonic Motor and an updated AF algorithm to quicken the autofocus operation while maintaining precision. The electromagnetic aperture mechanism makes it easy to adjust the exposure at fast continuous shooting rates. Also the nine diaphragm blades are rounded to create a smooth bokeh quality. The brass mount and rubber sealing add to the durable construction of the lens. An optional Sigma USB Dock can be connected to the lens for changing the focus settings or for firmware updates.