The Canon EF 28-70mm f/2.8 L USM is a professional grade fast wide angle zoom lens for Canon EOS Cameras. Introduced in 1993 as a major upgrade from the previous EF 28-80mm 2.8-4 L, the 28-70mm f/2.8 L USM is a ground breaking design that has lived up to and added to the reputation enjoyed by Canon L series lenses.
The highly corrected optical design of 16 elements in 11 groups produces images better than what many photographers were previously accustomed to from a lens in this zoom range.
Focus is fast thanks to a ring type USM (UltraSonic Motor) that features full time manual focus override.
The lens is designed so that the front optical assembly retracts as it is zoomed towards 70mm and extends when zooming towards 28mm. The EW-83IIB lens hood attaches to a stationary connection behind the moving front optical assembly. The stationary hood an moving front assembly work as a pair, shading the glass more effectively at longer focal lengths while shading less at shorter focal lengths so as not to vignetting the image.
When a replacement model was introduced in 2003 (the EF 24-70mm f/2.8 L USM), Canon mostly kept the same wildly succesfull optical and mechanical design. Other than a wider field of view and some dust sealing the 24-70mm f/2.8 L and 28-70mm f/2.8 L are near twins and a bit difficult to distinguish between. The original model remains popular and less expensive.
It's a great lens for any Canon EOS photographer looking for a versatile general purpose wide zoom lens that delivers excellent images.
Minimum aperture - 22 Close focus - 1.6' Length - 4 5/8 inches Weight - 1.9 lbs.