PDS_VERSION_ID          = PDS3                                                
RECORD_TYPE             = "STREAM"                                            
                                                                              
OBJECT                  = TEXT                                                
   INTERCHANGE_FORMAT   = "ASCII"                                             
   PUBLICATION_DATE     = 2022-06-30                                          
   NOTE                 = "                                                   
                                                                              
Worked example of calibration of LEISA observation                            
lsb_0397097519_0x53c_eng.fit.                                                 
                          "                                                   
END_OBJECT              = TEXT                                                
                                                                              
END                                                                           
                                                                              
Worked example of calibration of LEISA observation                            
lsb_0397097519_0x53c_eng.fit at (61,127,156), where the array                 
is assumed to start at 0 (i.e. IDL parlance).                                 
                                                                              
Raw file inputs:                                                              
S: raw input pixel value, after correcting for rollover = 393 DN              
I: integration time = 1.521 s                                                 
                                                                              
Calibration inputs from PDS nh-a-leisa-3-kem1-v4.0 deliv_20160331:            
E: electronics induced readout signal map pixel value, elecmap = 4.76119      
F: flat field map pixel value, flatmap.fit = 0.934652                         
O: offset map pixel value, calmap.fit, second band = 0                        
G: gain map pixel value, calmap.fit, first band Gain Correction = 3.2976e-5   
                                                                              
                                                                              
Equation for calibration, as per the calinfo.txt file:                        
                                                                              
                                      (S - E)                                 
                                  ( ( -------) - O ) * G                      
                                         F                                    
Calibrated Value at this pixel =  ----------------------                      
                                           I                                  
                                                                              
                                                                              
Substituting the values above into the calibration equation:                  
                                                                              
Calibrated Value at this pixel =    (393 - 4.76119)                           
                                 ((----------------)-0) * 3.2976e-5           
                         0.934652                                             
                           ----------------------------------                 
                                   1.521                                      
                                                                              
Calibrated Value = 0.0090057 erg/s/cm^2/Angstrom/sr                           
                                                                              
                                                                              
Value of this Pixel in the PDS calibrated file                                
lsb_0397097519_0x53c_sci.fit = 0.0090057 erg/s/cm^2/Angstrom/sr               
                                                                              
Thus, this calibration derivation agrees with the PDS calibrated file         
and data.