ESO Archive Frequently Asked Questions

Do a general search first, look at the result and use values from the result table to refine your query; gradually narrow down your search.
On the query forms one can select the columns that appear in the tabular output. So, mark all fields which are not displayed by default prior to the search and after looking at the result decide yourself which columns are crucial in the given context.
Browse also the programme (proposal) information and search for keywords or known authors to get references to particular observations that cannot otherwise be matched with some search criteria on a given form.
When querying for targets make sure the radius of the box around the target coordinates is large enough to cover the field of view of the instruments in which you are interested.
Consult the online help for a given field on a form if available.

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