With 2 Special Low Dispersion (SLD) elements to prevent chromatic aberrations, a newly-designed Hyper Sonic Motor (HSM) for fast, quiet, and stable autofocusing, and water/oil repellent coating, the Sigma 85mm f/1.4 Art DG HSM Lens is a fast f/1.4 prime lens designed to deliver outstanding resolution. Constructed from 14 lens elements in 12 groups, it promises beautiful, precise bokeh effects.