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FITS header

Here is an example of a typical FITS header from an APT image. It is designed to be fairly self-explanatory. The header keywords have been selected for compatibility with the IRAF packages ``ccdred'' from NOAO and ``gasp'' from STSDAS. The only problem is the non-standard use of ``BITPIX = -16''. Standard IRAF procedures can be used to automatically add the Julian Date, sidereal time, and airmass, to the header based on the information written by the APT.

SIMPLE  =                    T                                                  
BITPIX  =                  -16 / unsigned 16-bit integers                       
NAXIS   =                    2 / 2-dimensional image                            
NAXIS1  =                  100 / x dimension                                    
NAXIS2  =                  100 / y dimension                                    
BAXIS1  =                    1 / x binning factor                               
BAXIS2  =                    1 / y binning factor                               
DATASEC = '[1:100,1:100]'      / image section containing data                  
VERSION = 'MCCD version 2.1'   / version of the acquisition software used       
IMAGETYP= 'dark              ' / type of image                                  
SUBSET  = 'V                 ' / filter used                                    
OBJECT  = 'ngc6302           ' / the name of the object observed                
OBSERVER= 'Michael Ashley    ' / the name of the observer                       
RA      =          18.12320000 / right ascension [hours]                        
DEC     =         -33.44300000 / declination [degrees]                          
CRVAL1  =         210.56466666 / right ascension of reference position [degrees]
CRVAL2  =         -33.44300000 / declination of reference position [degrees]    
EQUINOX =             2000.000 / equinox of coordinates                         
EPOCH   =          1995.400049 / epoch of observations                          
CRPIX1  =                   50 / x coordinate of reference position [pixels]
CRPIX2  =                   50 / y coordinate of reference position [pixels]
XPIXELSZ=                 22.5 / x pixel size [microns]                         
YPIXELSZ=                 22.5 / y pixel size [microns]                         
PLATESCL=              419.111 / plate scale [arcsecs/mm]                       
XCOEFF1 =                      / 1st X coeff [arcsecs/mm]                       
XCOEFF2 =                      / 2nd                                            
YCOEFF1 =                      / 1st Y coeff [arcsecs/mm]                       
YCOEFF2 =                      / 2nd                                            
DATE-OBS= '15/05/1995'         / local date of observation [DD/MM/YYYY]         
TIME-BEG= '13:11:45.665'       / local time of exposure [HH:MM:SS.SSS]          
TIMEZONE=                   10 / local time - UT [hours]
EXPTIME =              120.000 / exposure time [seconds]                        
DARKTIME=              120.000 / total time since erased [seconds]              
CAMGAIN =                    1 / preamp gain [0 = low; 1 = high]                
CAMSHIFT=                    0 / number of bits shifted right                   
CAMSPEED=                    0 / readout speed [0 = low; 1 = high]              
CCDREAD =                  4.7 / readout noise [electrons]                      
CCDGAIN =                 10.2 / CCD gain [electrons/adu]                       
FOCUS   =                  120 / focus position [steps]                         
OBSERVAT= 'SSO         '       / observatory                                    
LAT_OBS =            -31.27336 / observatory latitude [degrees]                 
LONG_OBS=            210.93881 / observatory longitude [degrees]                
ALT_OBS =                 1149 / observatory altitude [meters]                  
TIMEZONE=                  -10 / observatory timezone [hours]                   
TELESCOP= 'AUTOMATED PATROL TELESCOPE'                                          
INSTRUME= 'WRIGHT CAMERA; EEV CCD; 770x1152'                                    
INSTITUT= 'UNIVERSITY OF NEW SOUTH WALES'                                       
EMAIL   = 'mcba@newt.phys.unsw.edu.au' / Michael Ashley's e-mail address        
WWW     = 'http://www.phys.unsw.edu.au/~mcba/apt.html' / WWW info on APT



Michael C. B. Ashley
Wed Jun 5 14:40:19 EST 1996