Acquisition and guiding

The spectrograph is mounted to the telescope by means of the 1.5-meter guider-acquisition module (GAM). This unit contains one TV camera on a motorized stage which can be used for field acquisition and offset guiding and a second fixed TV camera to view light reflected from the spectrograph slit jaws. The GAM probe accesses a 20cm square field ($1^\circ$ at f/7.5) although the field of view for the guide TV at any location covers approximately $2^\prime \times 3^\prime$. A leaky guider module is connected to the first of these cameras to facilitate (?!) automatic guiding.