One of a possible methods of collimating Starlight Express CCD cameras (SXV-M25C in my case) is to use Takahashi collimating scope.

The scope is attached to the front of the camera with a set of ca 50cm long extension tubes. One important requirements - all extension tubes have to be well made, concentric and with parallel faces as they could also introduce some shift.

This method is very simple and quick:
1. Attach the stack of extension tubes and collimating scope to the front camera plate.
2. Mount the camera vertically to avoid possible sagging or flexing of the stack.
3. Illuminated the collimating scope window with a flashlight mounted on photo tripod.
4. Focus the scope on the chip surface (not the camera window). This is easily done as one than can see the chip structure.
5. Look at the reflection of the scope illuminating circle - it should be concentric with the center of the chip - OK as there is no permanent mark on the chip, one need to judge the proper position.
6. Adjust the screws with a pair of Allen wrenches - one set of push-pull screws at a time. All adjustments are visible in real time.
7. Typically one will need to adjust only 2 sets of screws.
8. While adjusting the screw sets, try not to move the average chip position - to maintain overall camera backfocus.