The first Sigma 50mm f/1.4 DG HSM Art lens review was published by SLRgear and the upcoming Sigma lens was described as the second best 50mm full frame lens available today after the $4,000 Zeiss 55mm f/1.4 Otus Distagon T*:
The Sigma 50mm f/1.4 Art is the most exciting lens we’re likely to review this year. All competing lenses from Canon and Nikon fell short when compared to the resolving power of the 50mm Art. We haven’t (yet) tested the very best from Zeiss, but we are confident Sigma will trounce it in one key area: price.
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Put simply: it trounces any similar model available for less than $4,000. If it comes in significantly cheaper than the best of Canon and Nikon, Sigma will have made a friend of every full-frame shooter in the land.
The big question remains the price. SLRgear speculates that the price tag of the new 50mm Art lens will be under $1,700. This is the price range for the currently best offerings from Canon (the 50mm f/1.2L is $1,619.00) and Nikon (the 58mm f/1.4G is $1,696.95) but SLRgear also promises that the new Sigma lens will be a better performer (see MTF charts).