Changes
CCD'' item from the ''CCD'' drop-down menu. This will display
information regarding the bias reading and the maximum CCD count.
== Observing Recipe ==
1. Filling the cryostat
'''After filling the cryostat, you must wait 30 mins before beginning observations.'''
A technician will fill the cryostat at ~08:00 and ~16:00 (check on the log outside the Coude room that this has been done before you start observing). The observer must fill the cryostat either at ~19:00 and at the end of the night (avoiding the need to stop during observing), or at ~00:00, whether or not observations have been made.
The cryostat is filled from the dewar outside the Coude room. Check the pressure of the dewar - it should be ~10 bar, and must not exceed 15 bar. Open the right-hand blue tap to start filling, and watch the cryostat. Close the tap when liquid nitrogen starts to drip out of the cryostat.
The CCD "tank" temperature should be ~180K, and the "sink" temperature ~79K. The temperatures are displayed toward the bottom of the QUARTZ window.
'''Even in bad weather, the cryostat must be filled during the night.''' The last filling for the night should not be done before midnight.
