Skip to main content

Instrument-specific FAQ (FORS2) (Phase 2) - Knowledgebase / How to prepare your observations (Phase 2) / Instrument-specific FAQs (Phase 2) - ESO Operations Helpdesk

Instrument-specific FAQ (FORS2) (Phase 2)

Authors list

Frequently Asked Questions related to FORS2


  • Do I have to submit my MOS/MXU OBs at the same Phase 2 deadline as the pre-imaging OBs?

Answer:In case you have a scheduled pre-imaging run, your MOS/MXU OBs need only be submitted after the pre-imaging has been received.


  • When is the position of LADC (Longitudinal Atmospheric Dispersion Corrector) set?

Answer:LADC is set only once for any given OB and it is set at the beginning of the execution during object acquisition. It does not change during the whole execution of an OB. If a waiver for long OBs was granted (more than 1 hour), we recommend to ask for a manual adjustment of LADC position in your Readme file (which is done on a "best-effort" basis). For further info on LADC see FORS LADC webpage.