The Extended manual explains that better than I can
Have a look for that in the pinned threads in the TH sections...
In short, there is one switch that controls tilt mode, and the left rotary controls the tilt angle in both of them.
When the switch is in top position, left rotary directly controls camera tilt. At rotary minimum, the camera is pointing at ground, at maximum it points just above the horizon.
When the switch is in the down position, then rotary control now works around the centerpoint, and the camera can point up much further. In this mode, the rotary controls the speed of the tilt, up or down. The further away from center that control is, the faster your tilt will happen. To stop it, move it back to center.
Note: In the top switch position the camera won't tilt up enough to have the props in view, whereas in the lower position it will.
