Sigma 50mm f/1.4 DG HSM Art lens
I never would have thought I would say this just a year ago, but Sigma has smartened up and now designs good lenses, with their new ART series.
DXO Test's show conclusively that it out performs most other lenses.
So this only applies to the ART series of lenses, but its a good sign from a company known for producing marginal lenses, if I wanted to put a 50mm lens on my 5D today, it would be the Sigma.
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