The optical formula of the Canon EF 24-70mm f/4L IS USM integrates two aspherical and two UD glass lenses as well as an ultra-low dispersion lens, and benefits from a Super Spectra coating to ensure optimal contrast by fighting against glare and ghosting.
As an L series lens, the Canon EF 24-70mm f/4L IS USM’s optical formula is particularly well thought-out. Although many observers expected simply a stabilized version of the 24-70mm f/2.8, this stabilized 24-70mm sees the light of day at f/4. This more modest aperture will be less likely to generate a blurry background than if Canon had opted for f/2.8, but the lens still counts nine circular diaphragm blades with which to handle the bokeh.
The Canon EF 24-70mm f/4L IS USM embeds Canon’s latest hybrid optical image stabilization system, resulting in a gain of 4 stops, and iable to correct angular displacement and shift during macro photography. Its autofocus is powered by a USM system that allows for continuous adjustment.
The Canon EF 24-70mm f/4L IS USM’s finish is consistent with L series standards, and the zoom and the focus rings have been redesigned. The lens is tropicalized and resists both dust and moisture. It is possible to lock lens deployment while traveling, and both front and back lenses have been treated with a fluorine protective coating to keep them clean even in light rain or in dusty conditions.
The Canon EF 24-70mm f/4L IS USM will be available in January 2013 at a price of 1,699 euros.