Canon EF2470L2 EF 24-70mm F/2.8L II USM Ø82 Spanning a popular and versatile range of focal lengths the EF 24-70mm f/2.8L II USM is a Canon L-series zoom commonly thought of as the workhorse of lenses. Ranging from wide-angle to portrait length this lens is also distinguished by its constant f/2.8 maximum aperture to benefit working in difficult lighting conditions and to afford greater control over depth of field. The lens is also characterized by its sophisticated optical design which includes one Super UD element and two UD elements which reduce color fringing and chromatic aberrations in order to realize a high degree of color accuracy and clarity. Three aspherical elements are also featured and minimize distortion and spherical aberrations for improved sharpness. Additionally a Super Spectra coating has been applied to individual elements to control flare and ghosting for high contrast and neutral color fidelity. Balancing the refined optics this 24-70mm f/2.8 also sports a ring-type USM and internal focusing mechanism to enable quick quiet and accurate autofocus performance as well as full-time manual focus override. Additionally this lens is weather-sealed and has a protective fluorine coating on the exposed elements for use in trying environmental conditions. Standard zoom is designed for full-frame Canon EF-mount DSLRs however can also be used with APS-C models where it provides a 38.4-112mm equivalent focal length range. Bright constant f/2.8 maximum aperture affords consistent illumination throughout the zoom range and also affords greater control over depth of field for working with selective focus techniques. One Super Ultra-Low Dispersion element and two ultra-low dispersion glass elements noticeably reduce color fringing and chromatic aberrations for high clarity and color fidelity. Three aspherical elements minimize spherical aberrations and distortions for improved sharpness and accurate rendering. 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 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. Rounded nine-blade diaphragm contributes to a pleasing out of focus quality that benefits the use of shallow depth of field and selective focus techniques. Protective fluorine coating has been applied to the front and rear element to resist fingerprints and smudges and to make cleaning these elements significantly easier. As a member of the esteemed L-series this lens is sealed against dust and moisture for working in inclement environmental conditions. Zoom lock lever secures the zoom position at the wide end to maintain a compact form factor and protect the lens when not in use.