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Telescope Driving

After an object has been selected, the telescope slews as quickly as the hardware will allow to the object. When the telescope gets within a few hundred arcsecs it switches into a tracking mode and attempts to track to the demanded position as best as it can. Note that it takes a few seconds after tracking mode has been selected before the telescope is tracking sufficiently well for an exposure to begin. Check that things are sensible by looking at the diagnostic display which should be displaying numbers less than ten.

The telescope may be guided by means of either the handset attached to the telescope or the buttons on the control console.

The actions of the 'handset' buttons either on the observing floor or on the control console are determined by which mode is set on the SET/GUIDE/INCREMENT buttons on the console and by what value appropriate to each mode was set by the user interface. It is impossible to change modes from the observing floor.

The focus control buttons on the observing floor handset are under computer control when the handset is plugged into the 'Observer' socket which is normal. When the handset is plugged into the 'Engineering' socket the focus is under engineering control.

Tue Aug 5 05:37:08 MET DST 1997