The EF 70-200mm f/4L IS USM is a Canon L-series lens spanning a useful portrait-length to medium telephoto range. The constant f/4 maximum aperture allows you to maintain a consistent exposure throughout the zoom range and also contributes to the sleeker form factor when compared to other 70-200mm lenses. In regard to its optical performance, this lens employs one fluorite element and two ultra-low dispersion elements, which work in concert to suppress chromatic aberrations and color fringing for notable clarity and color accuracy. A Super Spectra coating has also been applied to control flare and ghosting for improved contrast when working in harsh lighting. this 70-200mm f/4 also features a four-stop-effective Image Stabilizer system that minimizes the appearance of camera shake for sharper handheld shooting. A ring-type USM and internal focusing mechanism also afford quick, quiet, and accurate autofocus performance, as well as full-time manual focus override. Constant f/4 maximum aperture affords consistent performance throughout the zoom range and also contributes to the relatively lightweight design and compact form factor. Super Spectra coating has been applied to individual elements to minimize ghosting and flare for greater contrast and color neutrality when working in strong lighting conditions. A ring-type Ultrasonic Motor (USM), along with an internal focusing system, is employed to deliver fast, precise, and quiet autofocus performance as well as full-time manual focus override.
Canon EF 70-200mm F/4L IS USM Specs