The Canon EF 24-70mm standard zoom lens does what many pros thought couldn't be done--it replaces the L-series 28-70mm f/2.8 lens with something even better. The lens offers extended coverage to an ultra-wide-angle 24mm, making it ideal for digital as well as film shooters. The new processing unit, meanwhile, makes the autofocus (AF) faster than ever. And thanks to the two aspherical elements and a totally new UD glass element, the optics are far superior to the earlier lens. Sealed and gasketed against dust and moisture, the EF 24-70mm lens carries a one-year warranty.
Pic : Canon EF 24-70mm f/2.8L USM Standard Zoom Lens for Canon SLR Cameras* Maximum aperture: 1:2.8
* Lens construction: 16 elements in 13 groups
* Diagonal angle of view: 74 to 29 degrees
* Focus adjustment: Front-focusing method
* Closest focusing distance: 1.25 feet
* Zoom system: Rotating type
* Filter size: 77mm
* Dimensions: 3.3 inches in diameter, 4.9 inches long
* Weight: 2.1 pounds
The Canon EF 24-70mm f/2.8 L USM Lens easily beats Canon consumer zooms (such as the Canon EF 24-85 Zoom Lens and the Canon EF 28-135 IS Zoom Lens) in direct sharpness and contrast comparisons.
Like most 24-xx zoom lenses, the Canon EF 24-70mm f/2.8 L USM Lens shows some barrel distortion on the wide end until disappearing around 35-40mm. This distortion is primarily evident on a full frame body. Vignetting is very well controlled, but apparent in the corners at f/2.8 at 24mm - primarily on a full frame body. Vignetting improves as the focal length increases and the aperture is narrowed. At comparable apertures, the 24-70 L shows less vignetting than the Canon EF 24-105mm f/4 L IS USM Lens- a typically expected result when comparing a fast lens to a slower lens. CA (Chromatic Aberration) is well controlled, generally only showing under harsh contrast conditions at the wide end of the focal length range.
A fixed f/2.8 minimum aperture makes this lens as fast as any Canon EF zoom lens made. The wide 8-blade aperture produces a nice background blur.
