OK, I realize these are very different lenses but both get a very, very similar score on DXO's lens compare (http://www.dxomark.com/Lenses/Compare/) when mounted on a Canon Mark ll. However, the 50mm is vastly less expensive. Additionally, you could take two shots side by side with the 50mm and stitch them together using a panorama program, such as the very reasonably priced PTGUI or Adobe Photoshop, and obtain a wider FOV than using the 35mm alone. So is there any reason to buy the more expensive Zeiss?