Distinguished by its fast design and IS capabilities, 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. Individual elements also feature an Air Sphere coating (ASC) to suppress lens flare and ghosting for greater contrast and color fidelity in backlit situations.Complementing the optical attributes, this lens also incorporates a four stop-effective optical image stabilization system that minimizes the appearance of camera shake for sharper handheld shooting. 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.This portrait-length L-series prime is designed for full-frame Canon EF-mount DSLRs, however can also be used with APS-C models where it will provide a 136mm equivalent focal length.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.One glass-molded aspherical element helps to reduce distortion and spherical aberrations for improved sharpness and clarity.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.A ring-type Ultrasonic Motor (USM), along with optimized AF algorithms, is employed to deliver fast, precise, and near-silent autofocus performance.Optical image stabilization minimizes the effects of camera shake by compensating for up to four stops of shutter speed.Full-time manual focus operation is available for fine-tuning of your focus position when working in the AF mode.Fluorine coatings on the front and rear surfaces help reduce fingerprints and smudging.A weather-resistant design protects the lens from dust and moisture to enable its use in inclement conditions.Nine rounded diaphragm blades contribute to a pleasing out of focus quality that benefits the use of shallow depth of field and selective focus techniques.