The Canon RF 28-70mm f/2 L USM is a wide-angle to portrait-length lens distinguished by its impressively unique f/2 constant maximum aperture. This bright design yields excellent low-light performance along with enhanced control over depth of field for isolating subject matter. Additionally, unique to RF lenses, this 28-70mm incorporates a configurable Control Ring for intuitively adjusting exposure settings, including ISO, aperture, and exposure compensation, from the lens itself. Impressively bright f/2 maximum aperture maintains consistent illumination throughout the zoom range and suits working in low-light conditions as well as affords increased control over depth of field for working with selective focus techniques. A ring-type Ultrasonic Motor (USM), along with an internal focusing design, optimized focusing algorithms, and a high-speed CPU, is employed to deliver fast, precise, and quiet autofocus performance as well as full-time manual focus override. As a member of the esteemed L-series, this lens has a weather-resistant design that protects against dust and moisture to enable its use in inclement conditions.