From the Carl Zeiss Lenses YouTube Channel:
The world's best wide-angle lens - ZEISS Otus 1.4/28
Uncompromising performance across the entire image field makes this full-frame lens unique and sets new standards among wide-angle focal lengths. Raise your photos to a totally new dimension by capturing even the tiniest details of your subject.
Note: Retail price of the lens has yet to be determined.