This circular fisheye lens captures a 180 degree angle of view giving you an exaggerated perspective and dramatic linear distortion. It produces full circle images when attached to a 35mm film SLR or full-frame digital SLR. When used with APS scaled sensors, image is cropped at the top and bottom of the frame when the camera is oriented horizontally.
It has a fast maximum aperture of f/3.5 and a minimum focusing distance of 5.3" makes this lens particularly useful for close-up photography. It also incorporates an auto focus system to help achieve focusing that might be difficult thought the camera's viewfinder due to the lens's extremely large depth of field.
Sigma's super multi-layer coating and Special Low Dispersion (SLD) glass reduces flare and ghosting, optimizing it for use with digital cameras and providing excellent image quality. A holder at the rear of the lens accepts gelatin filters.