There's a discussion on which is the sharpest wide angle on a D800. Some say these are the best out there:
For maximum sharpness, landscape wide angle lenses:
Distagon 21/2.8
Distagon 25/2
Nikon 28/1.8G
For 35mm the new Distagon 35/1.4
50mm Macro Planar.
These are the sharpest lenses.
Nikon 12-24 was mentioned as well.
Fyi.
Best lens for D800 for maximum sharpness? [Page 2]: Nikon D4 - D1 / D800 Forum: Digital Photography Review
For maximum sharpness, landscape wide angle lenses:
Distagon 21/2.8
Distagon 25/2
Nikon 28/1.8G
For 35mm the new Distagon 35/1.4
50mm Macro Planar.
These are the sharpest lenses.
Nikon 12-24 was mentioned as well.
Fyi.
Best lens for D800 for maximum sharpness? [Page 2]: Nikon D4 - D1 / D800 Forum: Digital Photography Review