Sigma’s new 105mm f/2.8 EX DG OS HSM macro lens is a redesign of an older design, with a few extra features. HSM focusing replaces an older (and slightly confusing) focusing system, and optical stabilization has been added in case you didn’t want to lug a tripod into the field
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Lens Review: Sigma 105mm f/2.8 EX DG OS HSM Macro
