Previous: Adjustment of the rotator axis and orientation.
Up: Observing with Fibres
Next: Calibration
Previous Page: Adjustment of the rotator axis and orientation.
Next Page: Calibration

Field acquisition

The first step to do when performing fibre optic multi-object spectroscopy is to select a field and to put the observing fibres on the aperture plate. To insert the fibres in the corresponding holes is an easy task but it must be performed with caution in order to avoid damaging the fibres ends. Also, it must be taken note of to which star in the field each fibre corresponds. Although it is not strictly needed it can be useful as well to order the stars by magnitudes, in such a way that --to avoid contamination-- two adjacent spectra do not produce large luminosity differences onto the detector. 10 to 15 minutes are required in order to insert 61 fibres in the plate.

Briefly, the field acquisition consists of pointing of the telescope towards the coordinates of the centre of the field to be observed. It is then expected that the 3 guide stars will appear correctly centred on the TV screen. Step by step this process is as follows:



Previous: Adjustment of the rotator axis and orientation.
Up: Observing with Fibres
Next: Calibration
Previous Page: Adjustment of the rotator axis and orientation.
Next Page: Calibration


Fri Jan 7 15:34:48 GMT 1994