Excerpted from the official EISA website:
“Sigma has created a lens that redefines portrait photography by combining an ideal focal length with technology that ensures top-quality results. Designed specifically for full-frame mirrorless cameras, its lightweight and compact body is distinguished by its excellent quality of construction, including dust and splash resistance. Users will enjoy sharp pictures without any aberrations thanks to the use of five SLD elements and one aspherical element, as well as the latest high-refractive index glass. Thanks to its f/1.4 maximum aperture, it produces beautiful artistic bokeh that will satisfy both professional and advanced amateur photographers.”