Two Super-Low Dispersion glass elements and two aspheric glass allow the proprietary optical design to achieve excellent contrast and sharpness as well as controlling chromatic aberration.
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 lens mount for manual focusing. The lens is also designed to stand up to the rigors of daily use by photographers in a wide variety of shooting conditions and environments.
Other than the optical coating change there are no changes to the Canon mount. The AT-X 116 PRO DX II for Canon uses the same AF motor and AF drive system as the the previous model.