While we're on the subject of great Zeiss lenses, you're gonna love the Distagon 15mm F2.8 in the Leica M mount. It's a beast of a lens, as you would expect for such a fast aperture.
Richard from Zeiss had one at the Henry's Imaging Show and let me play with it for a while. I had a chance to use one last year at a rally. This was shot on Delta 400. Most likely at F4 on Aperture Priority.
You can get the Zeiss lenses from bigcameraworkshops.com.