Next: Digits/Digits(axis) - Number of digits of precision
Up: AST Attribute Descriptions
Previous: DSBCentre - The central position of interest in a dual sideband spectrum
DefB1950
-
Use FK4 B1950 as defaults?
- Description:
- This attribute is a boolean value which specifies a default equinox
and reference frame to use when reading a FrameSet from a FitsChan
with a foreign (i.e. non-native) encoding. It is only used if the FITS
header contains RA and DEC axes but contains no information about the
reference frame or equinox. If this is the case, then values of FK4 and
B1950 are assumed if the DefB1950 attribute has a non-zero value and
ICRS is assumed if DefB1950 is zero. The default value for DefB1950
depends on the value of the Encoding attribute: for FITS-WCS encoding
the default is zero, and for all other encodings it is one.
- Type:
- Integer (boolean).
- Class Applicability:
-
FitsChan
-
All FitsChans have this attribute.
Next: Digits/Digits(axis) - Number of digits of precision
Up: AST Attribute Descriptions
Previous: DSBCentre - The central position of interest in a dual sideband spectrum
AST A Library for Handling World Coordinate Systems in Astronomy
Starlink User Note 210
R.F. Warren-Smith & D.S. Berry
24th May 2011
E-mail:ussc@star.rl.ac.uk
Copyright (C) 2009 Science \& Technology Facilities Council