As I mentioned in my last post, I bought an Nikon PC 24mm lens. This lens allows movements of shift and tilt; however, Nikon PC lenses have a problem especially for landscape photographers. When I shift a lens vertically, the lens can tilt only horizontally.
Landscape photographers use tilt and shift lens to avoid conversing lines which is seen when a camera is pointed up. Also landscape photographers like hyperfocal distance, images on focus from foreground to infinity. Tilt allows increasing the depth of field without closing down aperture. So it is more practical to set the movement of tilt and shift on the same axis.
So I had to modify the lens. Here is steps
1) Unscrew four screws on top of squire block of the lens. Micro screw did not work because screws were quite tight. I bought a screwdriver with large grip. 
2) Lift the top CAREFULLY since the top and lens body are connected with electronic cables. 
3) Rotate the top 90 degrees clockwise and screw the four screws back. 
4) Movements of the shift and tilt are the same axis.
I you want to try, please do it at your own risk.
Hiroaki Kobayashi's Blog 