IRAS Chopped Photometric Channel Images

Table 1 shows the header of the RAW version of one of the CPC_1711S77 images.

        Table 1.  Sample FITS header

SIMPLE  =                    T / SIMPLE FITS FORMAT ( HEADER VERSION D1 850214) 
BITPIX  =                   16 / PIXEL VALUES: 2-BYTE TWOS-COMPLEMENT INTEGERS  
NAXIS   =                    3 / NUMBER OF AXES IN THE DATA ARRAY               
NAXIS1  =                   42 / NUMBER OF PIXELS/ROW  (RA) (COLUMNS)           
NAXIS2  =                   57 / NUMBER OF ROWS        (DEC)                    
NAXIS3  =                    2 / NUMBER OF WAVELENGTHS (LAMBDA)                 
CTYPE1  = 'RA      '           /                                                
CRVAL1  =          2.57917E+02 / COORDINATE TRANSFORMATIONS:                    
CRPIX1  =          2.50000E+01 /  X OF PIXEL = ( COLUMN - CRPIX1 )*CDELT1       
CDELT1  =         -5.55556E-03 /  Y OF PIXEL = ( ROW - CRPIX2 )*CDELT2          
CTYPE2  = 'DEC     '           / TRANSFORMATIONS BETWEEN (X,Y) AND (RA,DEC):    
CRVAL2  =         -7.78167E+01 /  APPROXIMATE (FAR FROM THE CELESTIAL POLES):   
CRPIX2  =          3.30000E+01 /   X = (CRVAL1 - RA)*COS(CRVAL2)                
CDELT2  =          5.55556E-03 /   Y = DEC - CRVAL2                             
CTYPE3  = 'LAMBDA  '           /  EXACT:                                        
CRPIX3  =          1.00000E+00 /   X = SIN(CRVAL1 - RA)*COS(DEC)                
CRVAL3  =          5.00000E-05 /   Y = ( SIN(DEC)*COS(CRVAL2) ) -               
CDELT3  =          5.00000E-05 /       ( COS(DEC)*SIN(CRVAL2)*COS(RA-CRVAL1) )  
BSCALE  =          2.53505E-03 / DATA SCALE FACTOR (REAL=TAPE*BSCALE+BZERO)     
BZERO   =          9.34695E+01 / DATA OFFSET VALUE                              
BUNIT   = 'MJY / SR'           / BRIGHTNESS UNITS                               
BLANK   =               -32767 / TAPE PIXEL VALUE ASSIGNED TO UNDEFINED VALUE   
DATE-OBS= '29/03/83'           / DATE OF OBSERVATION       (JE 1983.241766)     
TIME-OBS= '13:18:13'           / TIME OF OBSERVATION                            
INSTRUME= 'IRAS-CPC'           / INSTRUMENT USED IN OBSERVATION                 
ORIGIN  = 'ROG-GRON'           / NAME OF INSTITUTE THAT PRODUCED THIS FILE      
OBJECT  = '             '      / NAME OF THE OBSERVED OBJECT                    
COMMENT  IRAS CPC RAW IMAGE :NO DEGLITCHING, NO GAINCORRECTION APPLIED.         
COMMENT                                                                         
COMMENT  START OF SCAN AT (COL,ROW)=(13,16) TO (COL,ROW)=( 4,42) IN 10 SECONDS. 
HISTORY  IMTOFTD1 850308 < RAWRGDD1 850126 < GAINCRD3 850126 < CPCATTD3 850126  
HISTORY  < DEGLTCD1 840920                                                      
COMMENT  THIS TAPE CONTAINS CONFIDENTIAL DATA                                   
COMMENT  PUBLICATIONS BEFORE DEC 1985 ARE RESTRICTED TO IRAS PROJECT SCIENTISTS 
DATE    = '08/03/85'           / CREATION DATE OF THIS FITS TAPE FILE           
END

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