The photographic plates find their full utility when a set of essential data is available. Also know as metadata, they are necessary to extract all "useful" informations.
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Enveloppe of a USNO plate with metadata. |
Many informations are important to ensure the accuracy of the analysis, and therefore the results: date, start time, exposure time, filters used, temperature, etc. We have identified, in the joint document, all necessary or optional data that allow to do the best use of a photographic plate, and that must go with the digitizations.