Sigma DC 17-50mm f/2.8 EX HSM OS lens. Canon EOS 450D: 12.2MP, Live View, fast autofocus, lightweight & easy to use. Sigma 17-50mm f/2.8: Excellent image quality, ideal walkaround zoom for landscapes, portraits, and general photography, constant bright f/2.8 aperture, Optical Stabilizer.
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