This Sigma EX f/2.8 Fisheye Fixed/Prime lens has 15 mm focal length. The DG/EX lens features auto focus and is designed to be used with SLR bodies and has a EF mount. It offers a 180 degree field of view, it has a minimum shooting range of 5.9 inches and a magnification ratio of 1 to 3.8. This lens has 6.9 cm in diameter and weighs 370 gram.