The EF 85mm f/1.4L IS USM from Canon is a short telephoto prime well-suited to portraiture applications. As an L-series lens, it is characterized by a sophisticated optical layout that includes one glass-molded aspherical element to greatly reduce spherical aberrations and distortion for improved sharpness and clarity. A ring-type Ultrasonic Motor (USM) also affords quick and accurate autofocus performance, along with full-time manual focus override for fine-tuned control. Additionally, as with all L-series lenses, this 85mm f/1.4 has a dust- and weather-resistant construction, as well as a fluorine coating on exposed elements, to benefit its use in harsh environmental conditions. Notably fast f/1.4 maximum aperture offers extensive control over depth of field for working with selective focus techniques. This bright design also benefits working in low-light conditions. An Air Sphere Coating (ASC) has been applied to lens elements to reduce backlit flaring and ghosting for maintained light transmission and high contrast in strong lighting conditions. Optical image stabilization minimizes the effects of camera shake by compensating for up to four stops of shutter speed. As a member of the esteemed L-series, this lens is sealed against dust and moisture for working in inclement environmental conditions.