Image formats other than FITS (SIA allows GRAPHIC types)?
Table formats other than VOTable (e.g. csv exports from apps are easy
and readable by TOPCAT)?
In general, I think a separate message for each format is probably safest - although Topcat is happy with csv, maybe Aladin isn't - although it's happy with votable. This gets more blurred with things like spectra - where there's many different formats, and representations for formats. So maybe it's a per-message-definition issue, not part of the messaging spec itself. -- NoelWinstanley
Do we need to send a data subset (i.e. rows from a table or image ROI only)?
Do we need to share access to data (rather than passing references and each app making a copy)?