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Optimisation of transient behaviours

The procedures described above (Section 2.2.2) can also be used to minimise transients during concatenated chains of similar observations. For example, consider the case of an observation in which the same ISOCAM configuration is used to observe several objects in a concatenated chain. Unless the special values of the DRK parameter are used, the instrument will go into parallel mode between each two successive observations in the chain. In that case, the observer would need stabilisation time to recover from the flux transient due to the change in configuration from the observing set-up to parallel mode and then back to the observing mode again. This can be avoided by using DRK=19 at the end of the first AOT, using DRK=29 in all of the intermediate steps, and using DRK=20 in the last AOT of the chain. Note that if the observer only uses ONE filter in the concatenated chain he or she will only have to stabilise the array in the first AOT. Nstab for all others can be set to 4.
When using this option, the user should be careful to insure that none of his observations will saturate. If the first or last source in the chain is brighter than about 0.6 Jy, dummy pointings at the beginning and end of the chain may also be needed.



Addendum of the ISOCAM Observer's Manual - V1.0
Mon Aug 5 15:50:39 MET DST 1996