Weeks ago we were told Sigma may soon announce new 70-200mm f/2.8 ART and 70-200mm f/4 CONTEMPORARY lenses. We were expecting the announcement before CP+. But nope.
The same source has now told us, Sigma has delayed the release of these new lenses until September, 2018. This makes us think Sigma is set for an announcement ahead of Photokina (September 2018). So far we have no hints about price and specifications.