Convert MaximDL default image type names to IRAF
image_type : str
Value of the FITS header keyword IMAGETYP; acceptable values are below in Notes.
str
IRAF image type (one of ‘BIAS’, ‘DARK’, ‘FLAT’ or ‘LIGHT’)
Notes
The MaximDL default is, e.g. ‘Bias Frame’, which IRAF calls ‘BIAS’. Can safely be called with an IRAF-style image_type.