Sigma 85mm f/1.4 DG HSM, ideal for portrait photography both in-studio and on-location. The new Hyper Sonic Motor (HSM) allows 1.3x the torque of previous generations for efficient and quick autofocus. The 9 blade rounded diaphragm creates beautiful background bokeh to isolate and accentuate the subject. Multi-layer coating applied to lens elements minimize lens flare and ghosting and produce contrast-rich and color-neutral pictures even in backlit conditions. Designed for Full-frame DSLR cameras. Also used with APS-C models in which it will give 136mm equivalent focal length.