Compatibility between FITS and GILDAS

The notable projections supported by GILDAS are summarized in the Table 2.

Table 2: List of the projections implemented in GILDAS and subject to export or import to/from FITS data format. The top group was defined in the AIPS memo 27, the middle group in the memo 46, and the bottom group in the CG02 paper.

Name	FITS	GILDAS	Note
Gnomonic	TAN	gnomonic	Full compatibility GILDAS/FITS
Slant orthographic	SIN	orthographic	Basic compatibility (GILDAS does not implement the additional SIN projection parameters)
Zenithal equidistant	ARC	azimuthal	Full compatibility GILDAS/FITS
North Celestial Pole	NCP	ncp	Deprecated in FITS, kept in GILDAS as this would require additional projection parameters of the SIN projection
Stereographic	STG	stereographic	Full compatibility GILDAS/FITS since aug23 (see section 2.5)
Hammer-Aitoff	AIT	aitoff	Compatibility GILDAS/FITS as long as the reference is on the Equator
Global-Sinusoidal	GLS	radio	Compatibility GILDAS/FITS but deprecated in FITS, translated to SFL with translation
Sanson-Flamsteed	SFL	sfl	Full compatibility GILDAS/FITS since oct23 (see section 2.8)