Raw data produced from LCOGT Network telescopes are in Rice-compressed ("fpacked") FITS format. Data processed by the (BANZAI) reduction pipeline are in FITS file format with two extensions: a source catalog (CAT) in a FITS binary table and a bad pixel mask (BPM) in an array. Library calibration frames (e.g. master bias/dark frames, flat fields, shutter correction and fringe frames) are also available in the Science Archive.
Processed frames follow a prescribed format given by the “Data Dictionary for LCOGT FITS files (LCOGT-FITS-PIPE.DIC)” (a HTML table version of this is given at FITS headers) with images corresponding to a single detector frame (all current LCOGT cameras) stored in a single HDU with the data pixels written into the primary data array. Derived source catalogs corresponding to each image are written as FITS binary tables. The headers for the catalog MEF contain all the information of image MEF headers plus ancillary processing keywords and values. The bitmap images are in PNG format with a size of 512x512 and contain some limited astronomical metadata to the AVM standard.
Physical units used match the SI quantities and derivatives with some exceptions for those in regular astronomical use. Celestial co-ordinates are expressed in the system specified by the primary HDU keyword RADESYS; this is defined to be ’ICRS’ for the lifetime of LCOGT data. The EQUINOX keyword is not provided, as it is formally incorrect to associate a date/equinox with a kinematically non-rotating reference system such as ICRS. World Co-ordinate System (WCS; i.e. astrometric) information uses the set of standard keywords described in the FITS WCS standards.