Based on the award-winning optical design of the AT-X 124 PRO DX (12-24mm f/4) lens, the new AT-X 116 PRO DX has a slightly shorter zoom range to maintain optical quality at wide apertures.
Tokina's inovative One-touch focus-clutch mechanism allows the photographer to switch between AF and MF simply by clicking the focus ring forwards for auto- or back towards the camera for manual-focus (there is no need to change the AF-MF switch on the body of compatible, although the lens is restricted to MF with D40 and D40x cameras).