The Sigma 15-30mm F3.5-4.5 EX DG Aspherical DG Lens provides focal lengths from 15mm ultra-wide angle to 30mm wide-angle, and has a minimum focusing distance of 11.8" at all focal lengths with 110.5Deg (wide) to 71.6Deg (telephoto) of angle view. Features a hybrid aspherical lens in the front lens group to minimize distortion and astigmatism, and molded glass aspherical lens in the rear lens group to minimize spherical aberration. This lens is equipped with a dual focus mechanism and an inner focusing system, and its easy to hold, since the focusing ring does not rotate during auto focusing. Its effective zoom range is 22.5mm-45mm on most SLR digital cameras. For use with Canon cameras.