OFF AXIS GUIDER SHORT OFF AXIS - THE ALTERNATIVE TO THE GUIDE TELESCOPE
This very short off-axis guider is a practical alternative to conventional separate guide scopes for using a DSLR or CCD camera for astrophotography and offers a number of advantages.
More precise tracking as mechanical flexibility and image shifts are kept away from the system. The recording camera and the guiding camera are always moved in exactly the same way.
The entire system is significantly lighter and more compact than a separate guide scope.
Brighter and higher resolution images of the guide star on the guiding camera because the main telescope is used. This makes it easier to identify and compensate for tracking errors.