Canon EF 24-70mm f/4L IS USM Overview
Blending a flexible zoom range with a versatile feature-set, the EF 24-70mm f/4L IS USM is a Canon L-series lens covering wide-angle to short telephoto focal lengths and featuring a constant f/4 maximum aperture. An advanced optical layout comprises two ultra-low dispersion elements and two aspherical elements to minimize a variety of aberrations and distortion in order to realize notable sharpness and clarity. A Super Spectra coating has also been applied to suppress lens flare and ghosting for greater contrast and color accuracy.
Complementing the optical performance, the lens is also characterized by its ring-type USM and internal focusing mechanism to enable quick, quiet, and precise autofocus performance along with full-time manual focus override. A dedicated macro position also enables focusing as closely as 7.9" away in order to achieve a 0.7x magnification for photographing close-up subjects. A four-stop-effective Image Stabilizer is also used to minimize the appearance of camera shake for sharper handheld shooting. Additionally, this lens is weather-sealed and has a protective fluorine coating on the exposed elements for use in trying environmental conditions.