The Schneider PC TS Super-Angulon 50mm f/2.8 Lens (For Nikon) gives you the same types of controls used by large format cameras to control perspective, but for your Nikon camera. There's both a parallel shift to reduce or eliminate converging lines or perspective distortion ("keystone correction") and a swinging or tilting of the lens according to Scheimpflug's rule to better utilise depth of field (DOF) without an increase in diffraction from stopping down the aperture further and reducing sharpness.