The staple Sigma 50mm 1.4 DG HSM has been 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 1.4 is a high performance lens for the modern DSLR sensors.
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