Tokina
For the professional, a 16-28mm f/2.8 lens is almost a necessity, and this new AT-X 16-28mm f/2.8 Pro FX Lens for Canon from Tokina fills the bill very nicely. Designed specifically for Canon pro level DSLRs with a full frame (FX) sensor (such as the Canon EOS 5D Mark II), this super wide-angle zoom has 15 elements in 13 groups, using aspherical and SD super-low dispersion glass elements to reduce chromatic aberration and give maximum resolution. The silent DC motor allows the lens to focus quickly and quietly and works with a GMR magnetic AF sensor to increase AF speed even more. An exclusive One-Touch Focus Clutch mechanism allows switching quickly between auto focus and manual focus by snapping the focus ring forward for AF and back toward the camera for manual focus. And, it's possible to buy this lens without applying for a mortgage first.
Designed for professional full frame (FX) Canon DSLRs.
The 16-28 f/2.8 uses a newly developed silent DC motor that allows the lens to focus faster and more quietly then previous generations. The DC motor coupled with a new GMR magnetic AF sensor work together to increase AF Speed.
A new, 56mm-diameter, large size aspherical glass element is incorporated into the front lens group, while there are 2 more aspherical elements in the rear group. 3 SD super-low dispersion glass elements are also incorporated throughout the optical design to reduce chromatic aberration, give maximum resolution, more even brightness and distortion correction.
Tokina's exclusive One-Touch Focus Clutch Mechanism allows the photographer to switch between AF and MF simply by snapping the focus ring forward for AF and back toward the camera to focus manually. There is no second AF/MF switch on the lens for Canon, everything is accomplished with the focus ring.