Previous: Field acquisition
Up: Observing with Fibres
Next: Data reduction
Previous Page: Field acquisition
Next Page: Data reduction

Calibration

The calibration lamp for the fibre system is not yet driven from the A&G box 4ms microprocessor, although it is planned to implement this diring 1993. At present the power to the calibration lamp will need to be switched on by the observer, usually from one of the power points on the inside of the telescope fork. To take a calibration exposure all of the A&G box mirrors must be withdrawn with the ICL command AGMIRROR OUT. The frequency recommended for calibration exposures depends upon the specific application, and is the same as that for normal CCD observing. The calibration lamps are bright, and only short exposures (1-5 seconds) are required. The gain of the TV systems must be turned down while calibration exposures are in progress.