The Canon EF-mount Tokina atx-i 100mm f/2.8 FF Macro is a short telephoto macro lens, offering a life-size, 1:1 maximum magnification along with an 11.8" minimum focusing distance. This lens uses a flat-field optical design to yield realistic rendering, void of field curvature, as well as high sharpness and clarity throughout the focusing range. A multilayered coating has also been applied to reduce lens flare and ghosting for increased contrast and improved color fidelity. This short-telephoto prime is designed for full-frame Canon EF-mount cameras, however, can also be used with APS-C models where it provides a 160mm equivalent focal length. Flat-field optical design helps to greatly reduce field curvature in order to realize consistent, edge-to-edge sharpness and illumination throughout the aperture and focusing ranges. The Autofocus system offers fast, precise focusing capabilities and a One-Touch Focus Clutch Mechanism avails quick switching between autofocus and manual focus settings by either pushing or pulling the focus ring. When set to manual, focus response is especially smooth and benefits from hard stops at the ends of the focusing range.