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Sigma 500mm f/4.5 EX DG IF HSM APO Telephoto Lens for Canon SLR Cameras

Product Description :
Fast maximum aperture telephoto lens optimized for digital SLR cameras
Most effective coating for minimizing flare and ghost
Two Extraordinary Low Dispersion ELD glass elements produce excellent image quality
Accepts both 14X and 2X APO EX Tele-Converters The lens can be used as a 700mm MF or a 1000mm MF ultra-telephoto lens