And none will be available today; Sigma says the 18-50mm F2.8 will go on sale this summer, with the remainder of its introductions set for the fourth quarter. The Tamron 11-20mm is slated for ...

The edges do almost as well, with low figures that are a credit to Sigma for such a wide-angle ... which is pretty good for a 20mm lens. Further correction is possible in-camera or in software ...

Sigma 20mm F/1.4 DG DN Art Verdict There are some terrific ultra-wide primes around, and the Sigma 20mm f/1.4 DG DN Art lens is definitely up there with the best. It's true that 20mm is quite wide ...