Tokina 12-28mm f4 Pro DX Nikon

New Optical Design A new optical design using aspherical elements and super-low dispersion glass matches even the highest mega-pixel DX sensors cameras available today. One aspherical lens element is positioned in the front group. This together with another precision molded glass aspherical lens element placed in the rear group ideally focuses marginal light rays and maintains sharpness at the edges while also correcting distortion. The use of two different SD(Super-low Dispersion)glass elements, typeFK01 and FK03, corrects chromatic aberration. The combination of all these specialized elements in the optical design yield excellent sharpness and color. New auto focus mechanism The new AF “GMR magnetic precision” control sensor is capable offastauto-focus. Tokina placed the new sensor closer to the drive unit in the lens for faster communication between the controller and AF motor. This combined with the motor's high-precision focus control yields faster, more accurate auto-focus. Additionally, a brand new “SD-M” (Silent Drive-Module) has greatly lowered the sounds emitted by the auto focusdrive system allowing for much quieter AF. Both Canon and Nikon mounts have a built-in AF motor to make them auto-focus compatible with all current camera bodies. Compact body design The Tokin AT-X 12-28mmF/4 compact design makes the lens easy to carry and handle. Manual focus is achieved through Tokina's one-touch focus clutch AF/MF mechanism. Simply slide the manual focus ring forward for auto-focus or back for manual focus operation. The lens focus ringis damped in the manual mode for smooth and precise focusing.