Previous: Preparing for observing
Up: Operation of FOS and astronomical considerations
Next: Other variables
Previous Page: Preparing for observing
Next Page: Beam switching or not?

FOS observing modes

By now you should have decided on which of the 4 possible FOS observing modes to use. These modes are selected by selecting a dekker and field lens configuration via the commands

ADAM> DEKKER M

ADAM> BSCF N

See appendix A for details of the different choices.

It is straightforward to change between these modes, so you can change as often as necessary during a night to suit your requirements. The 4 modes are:

Mode A: Beam switching point sources with 5", 2", or 1.2" slots, 12" apart both orders

Mode B: Beam switching extended objects with 25"slots, 85" apart, both orders

Mode C: Long slit, 200" slot, first order only

Mode D: Single object, 25" slot , both orders.

The format of the data taken in these modes is shown in appendix A figure A.1. Choosing between the modes depends on a variety of factors and personal preferences. The most commonly used modes of observing are Modes C and D.



Tue Apr 12 04:13:28 BST 1994