According to the recent rumors, Sigma will announce a new Ultra Wide-angle zoom Art lens in late 2015. It is rumored to be a replacement to the Sigma 12-24mm f/4.5-5.6 DG II.
Several weeks ago, Canon announced the EF 11-24mm f/4L USM lens for &2,999. It is a great lens except the price. Sigma new art lens will be much cheaper than Canon EF 11-24mm f/4L.
Source:CR
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