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Reference

For each spectrum, the Class Data Format expects a reference (usually source) position. In MRTCAL, this reference is taken from the LONGOBJ and LATOBJ (Source longitude and latitude in basis frame) in the Scan HDU.

From this reference, the IMB-FITS format can define an intermediate reference position, through the SYSOFF, XOFFSET and YOFFSET columns in the Scan table:



Gildas manager 2015-03-19