Tokina 11-16mm F/2.8 AT-X116 Pro DX II Digital Zoom Lens (For Nikon)

F2.8 a slightly shorter zoom range to maintain optical quality at wide apertures and has an internal silent focusing motor to allow the lens to af on nikon bodies that do not have an af drive gear and motor. One touch focus clutch: tokina's 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 need to change the af-mf switch on nikon cameras and there is no second af/mf switch on the lens for canon, everything is accomplished by the focus ring.