next up previous contents
Next: Observations Up: A typical observing night Previous: Preparing the observing night   Contents

Setup and flat fields

Setup: You may setup the telescope during day-time as described in Section 2, but leaving the slit and the main mirror cover closed.

Dark current: You may wish to make dark exposures with a range of exposure times to obtain corrections for the dark current (cf. Section 4.1).

Ventilation: You may open the slit and the doors of the dome after sunset to allow adjustment of temperatures inside the dome to the ambient temperature. Keep the doors to the lower floors strictly closed.

Flat-fields: Open slit and the main mirror cover and proceed with flat-field observations (cf. Section 4.2).



Dieter Engels
2003-01-15