NAME

       mHdrCheck - Check the validity of a FITS image's header

SYNOPSIS

       mHdrCheck [-s statusfile] img.fits

DESCRIPTION

       mHdrCheck  reads  in  the  header from a FITS image (or an ASCII header template file) and
       checks to see if any header lines are invalid.  If it finds  one,  it  will  print  out  a
       message  stating which keyword is invalid and exit before checking the rest of the header.
       It will not report on multiple invalid values.  If all value are correct,  mHdrCheck  will
       print out a "Valid FITS/WCS" message.

OPTIONS

       -s statusfile
              Output and errors are sent to statusfile instead of to stdout

ARGUMENTS

       img.fits
              Path of FITS file to be validated.

MESSAGES

       OK     Valid WCS in FITS file.

       OK     Valid FITS/WCS in header file.

       ERROR  Cannot open status file statusfile

       ERROR  File filename not found.

       ERROR  File (filename) is not a FITS image

       ERROR  FITS header lines cannot be greater than 80 characters

       ERROR  No BITPIX keyword in FITS header

       ERROR  No NAXIS keyword in FITS header

       ERROR  No NAXIS1 keyword in FITS header

       ERROR  No NAXIS2 keyword in FITS header

       ERROR  No CTYPE1 keyword in FITS header

       ERROR  No CTYPE2 keyword in FITS header

       ERROR  No CRPIX1 keyword in FITS header

       ERROR  No CRPIX2 keyword in FITS header

       ERROR  No CRVAL1 keyword in FITS header

       ERROR  No CRVAL2 keyword in FITS header

       ERROR  No CDELT1 keyword (or incomplete CD matrix) in FITS header

       ERROR  No CDELT2 keyword (or incomplete CD matrix) in FITS header

       ERROR  BITPIX keyword in FITS header not an integer

       ERROR  Invalid BITPIX in FITS header (must be 8,16,32,64,-32 or -64)

       ERROR  NAXIS keyword in FITS header not an integer

       ERROR  NAXIS keyword in FITS header must be >= 2

       ERROR  NAXIS1 keyword in FITS header not an integer

       ERROR  NAXIS1 keyword in FITS header must be > 0

       ERROR  NAXIS2 keyword in FITS header not an integer

       ERROR  NAXIS2 keyword in FITS header must be > 0

       ERROR  CRPIX1 keyword in FITS header not a real number

       ERROR  CRPIX2 keyword in FITS header not a real number

       ERROR  CRVAL1 keyword in FITS header not a real number

       ERROR  CRVAL2 keyword in FITS header not a real number

       ERROR  CDELT1 keyword in FITS header not a real number

       ERROR  CDELT2 keyword in FITS header not a real number

       ERROR  CROTA2 keyword in FITS header not a real number

       ERROR  CD1_1 keyword in FITS header not a real number

       ERROR  CD1_2 keyword in FITS header not a real number

       ERROR  CD2_1 keyword in FITS header not a real number

       ERROR  CD2_2 keyword in FITS header not a real number

       ERROR  EQUINOX keyword in FITS header not a real number

       ERROR  No WCS information (or not FITS header)

       ERROR  Must have at least two dimensions

       ERROR  Invalid projection

       ERROR  Invalid NAXIS1

       ERROR  Invalid NAXIS2

       ERROR  CTYPE1 and CTYPE2 don't match

       ERROR  Invalid CTYPE1

       ERROR  Invalid CD matrix

       ERROR  Invalid CDELT1

       ERROR  Invalid CDELT2

       ERROR  FITS library error

EXAMPLES

       $ mHdrCheck input/badfits/bad-crota2.fits
              [struct stat="ERROR", msg="CROTA2 keyword in FITS header not a real number"]

       $ mHdrCheck input/2mass.fits
              [struct stat="OK", msg="Valid FITS/WCS."]

       $ mHdrCheck input/badfits/bad-ctype.fits

              [struct stat="ERROR", msg="Invalid projection"]

BUGS

       The drizzle algorithm has been implemented but has not been tested in this release.

       If  a  header  template  contains  carriage  returns  (i.e., created/modified on a Windows
       machine), the cfitsio library will be unable to read it properly, resulting in the  error:
       [struct stat="ERROR", status=207, msg="illegal character in keyword"]

       It  is  best  for the background correction algorithms if the area described in the header
       template completely encloses all of the input images in their entirety. If parts of  input
       images  are  "chopped  off"  by  the  header  template,  the background correction will be
       affected. We recommend you use an expanded header  for  the  reprojection  and  background
       modeling  steps, returning to the originally desired header size for the final coaddition.
       The default background matching assumes that there are no non-linear background variations
       in  the  individual  images  (and  therefore  in the overlap differences). If there is any
       uncertainty in this regard, it is safer to turn on the "level  only"  background  matching
       (the "-l" flag in mBgModel.

COPYRIGHT

       2001-2015 California Institute of Technology, Pasadena, California

       If  your  research  uses  Montage,  please  include  the  following acknowledgement: "This
       research made use of Montage. It is funded by the National Science Foundation under  Grant
       Number  ACI-1440620,  and  was  previously  funded  by  the National Aeronautics and Space
       Administration's Earth Science Technology Office, Computation Technologies Project,  under
       Cooperative  Agreement  Number  NCC5-626  between  NASA  and  the  California Institute of
       Technology."

       The Montage distribution includes an adaptation of the MOPEX algorithm  developed  at  the
       Spitzer Science Center.