12" RC Collimation

Collimating. Some short preliminary notes.

The Ritchey-Chr├ętien instrument design has two hyperbolic mirrors. They need to be collimated with high precision. Here are some notes for my setup. 

1. Mount the laser collimator in the rotatable focuser. I use a standard Hutech collimator.

2. By rotating the focuser, make sure the laser spot on the secondary mirror is stationary and that the rotation is not letting the spot move. I note that the friction clutch on the focuser must be slightly tightened, otherwise you get some minor shift of the focuser axis, when the focuser is rotated.

3. Then make sure the rotation is locked, also the friction screw.

4. Adjust the tilt of the focuser, so the laser spot is centered in the small ring in the center of the secondary.

5. Adjust the secondary's screws, so the reflection onto the 45 degree plate on the Hutech collimator is centered.

6. Align the main mirror.

   ... to be continued...