The Tokina AT-X 107 DX, For Nikon is a fish-eye lens that gives the digital photographer an approximate 180 Deg 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. Unlike other fish-lenses, the AT-X 107 DX gives a full corner-to-corner image.  The front element of the AT-X 107 DX has a newly formulated WP or AgWater ProofAh 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.
Note: This lens is designed to work with cameras that have an APS-C sized sensor only.

Specifications:

Mount availability: Canon EOS, Nikon-D
Focal length: 10 to 17mm
Maximum aperture: f/3.5-4.5  
Minimum aperture: f/22 
Optical construction: 10 elements in 8 groups 
SD glass: One elements 
Coatings: Multi-layer 
Angle of view: 180 Deg  to 100 Deg 
Minimum focus distance: 5.5 in. (14 cm) 
Reproduction ratio: 1:2.56 
Zooming system: Rotary type 
Number of diaphragm blades: 6 
Filter size:  N/A 
Maximum outer diameter: 2.75 in. (70mm) 
Dimensions: 2.75 in. (70mm) X L 2.79 in. (71.1mm) 
Weight: 12.3 oz. (350g)