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Do I need dedicated calibration? If yes, how many calibration OBs do I have to submit? - Knowledgebase / How to prepare your observations (Phase 2) / Service Mode - ESO Operations Helpdesk

Do I need dedicated calibration? If yes, how many calibration OBs do I have to submit?

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Do I need dedicated calibration? If yes, how many calibration OBs do I have to submit?


The most commonly used observing configurations of each instrument are calibrated by means of the Observatory's Calibration Plan. Calibration Plans for each instrument and mode are described in detail in their corresponding User Manual, and their execution times are not charged to the Service Mode programmes.

If a special calibration is needed, please check here to have additional information.

If this, is the case, to estimate how many calibration OBs to submit, you should assume that your science OBs will be executed completely independently of each other, possibly on different nights, and take into account that no calibration OB will be executed more than once. You should submit enough special calibration OBs to cover that situation. Example: if you need to observe and flux-calibrate six targets in a filter that is not supported in the calibration plan of the instrument, you need to provide six special calibration OBs to allow for the case in which each target is observed on a different night. This must be done so even if the same calibration star can be used for all the science targets. Whenever possible and if this suits your needs, you might consider to concatenate your calibration and science OBs in a concatenation container (see this article for more details), to make sure they will be observed during the same night. For assistance, contact the User Support Department through the helpdesk system.