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Instrument-specific FAQ (SPHERE) (Phase 2) - Knowledgebase / How to prepare your observations (Phase 2) / Instrument-specific FAQs (Phase 2) - ESO Operations Helpdesk

Instrument-specific FAQ (SPHERE) (Phase 2)

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Frequently Asked Questions related to SPHERE


  • I do not want to use a coronagraph. How do I specify this in P2?
  • Answer: For SPHERE, the coronagraph is defined in the acquisition template. For the ZIMPOL_I, ZIMPOL_P1 and ZIMPOL_P2 modes selecting "V_NC_WF", or "V_NC_NF" will select no coronagraph, with the wide field and narrow field collimator, respectively. For the IRDIFS, IRDIFS_EXT, IRDIS_CI, IRDIS_DBI and IRDIS_DPI modes, the selection "N_NS_CLEAR" inserts a clear mask instead of a coronagraph. It is not possible to use the IRDIS_LSS mode without a coronagraph.



  • Why do I need to specify a star-center observation in all coronagraphic OBs?
  • Answer: The SPHERE data-reduction pipeline needs a star-center observation to be able to reduce coronagraphic data. Even if you are using your own procedures instead of the pipeline, the pipeline still needs to be able to run on your data to perform quality control at the telescope.