The new Tokina AT-X 107 is a fish-eye lens that gives the photographer a 180 to 176 degree field of view with dramatic curvature of field or fish-eye effect. With this lens an entire view or vista can be captured, wider than the human eye can see. The AT-X 107 opens an entirely new dimension of photography. The front element of the AT-X 107 DX has a newly formulated WR or Water Repellent" optical coating on the glass. This new coating makes marks such as spots left by water or finger-prints much easier to clean than standard multi-coating.** The rear optical group of the lens contains 1 SD (Super-Low Dispersion) glass element to reduce the number of elements (pieces of glass) in the optical design in order to make the lens more compact, light-weight and faster focusing.