Amazon.com : Sigma 311101 50mm F1.4 DG HSM Art Lens for Canon Cameras : Camera & Photo

50mm F1.4 DG HSM ART- redesigned and reengineered to set a new standard for the Art line. A Hyper Sonic Motor (HSM) ensures quiet, smooth and accurate autofocusing and paired with Special Low Dispersion (SLD) glass and Super Multi-Layer coating, the 50mm

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