EF 20-35mm f3.5-4.5 USM
The EF 20-35mm f3.5-4.5 USM, gives EOS users a highly versatile entry to the exciting possibilities of ultra-wide-angle photography. In fact, it covers the same focal range as the EF 20-35mm f2.8L, but in a more compact design.
The autofocus drive uses a ring-type USM motor which gives near silent, high speed focusing. Lens construction is 12 elements in 11 groups with an inner focusing system. This means that the length of the lens does not change during focusing or zooming. Also, the front of the lens does not rotate, making polarising filters easier to use.
Image quality is further enhanced by the use of a frame-sized, flare cutting diaphragm positioned in the first lens group. Focusing is down to 34cm at all focal lengths, with manual focusing possible in AF mode.
Focal length and maximum aperture: 20-35mm 1:3.5-4.5