PIA data reduction for P40
------------------------------
(details about the individual correction/processing
 algorithms can be found in:
 http://www.iso.vilspa.esa.es/manuals/PHT/pia/um/processing.html)


ERD level:
 * Non-linearity correction
   (not available for P40)

 * Read-out deglitching
    --> Test processing
        --> Test deglitching (single or 2 Threshold method)
            --> Accept & Quit
    --> Correction
        --> Read-out simple deglitching or 2 Threshold deglitching

    (Cosmic particles hit the detector pixels with such energy, that
     the voltage ramps are seriously disturbed: local 'jumps' between
     2 read-outs, or even 3 read-outs, and an immediate relaxation.
     the information redundancy on voltage differences between
     read-outs allows us to pick out those anomalous jumps and to
     correct the ramps affected. The 2 Threshold deglitching is
     more efficient.)

 * Saturated Ramps
   --> Correction
        --> Change Saturation Params
   (Integration of a ramp above the saturation limit (~ 1.2 V)
    is not possible. An automatic recognition for all cases has
    been introduced in PIA. Changing the Parameters is usually
    not necessary.)

 * Raster point ID correction for tracked SSO observations
   --> Correction
        --> Set RPID -> [1,1]
   (PIA considers now the measurement as tracked observation.
    PIA does not automatically recognize the tracking mode, since
    it is performed in the same way as rasters.)

 * Ramp fitting
   --> Process Measurement
       --> Fit ramps
           --> 1st order Pol.

SRD level:

 * Reset interval correction
   (not applicable at the moment)

 * Signal Deglitching
   --> Correction
       --> Deglitching
           --> Customize: 2 Iterations (or more), Use max/min clipping
   --> Correction
       --> Deglitching
           --> Perform it
   (There is also the posibility to do the deglitching manually
    for each pixel:
    --> Test processing
        --> discard area graphically)

 * Dark current subtraction
   --> Correction
       --> Dark current subtr. (orbital dep.)
           --> Customize: Interpolate one value per data point, ok
   --> Correction
       --> Dark current subtr. (orbital dep.)
           --> Perform it
           
   (Dark currents exist for every detector pixel, binned
    reflecting the dependence of the dark currents on the orbital
    position. For several detectors (mainly Ge:Ga) the cosmic hit
    radiation plays a dominant role and changes the dark currents
    with orbit position.)

 * Signal derivation
   --> Process
       --> dynamic calibration
           --> customize & perform: select 2 or more standard stars
                                    (deselect late type stars)

   (The basic assumption of the dynamic calibration is that the
    transients behaviour (eg temporal response) of an individual pixel
    depends primarily on the flux level observed with a high
    reproducibility under a similar illumination history of the detector.
    A comparison of the signals achieved by the target to the ones
    achieved by different calibrators after same time intervals within
    an observation allows a discrimination of the nearest calibrators
    in flux to the target. The ratios obtained are then used for
    deriving the unknown target flux.
    A deselection of late type stars (K2 and later) from the list of
    standards is in some cases recommended. Late type stars show the
    fundamental SiO absorption band (between 7 and 9.5 micron), which
    seems to be not well modelled.)

 
Dynamic Calibration Data Display

 * Flux Calibration
   --> Process
       --> Combine all calibrators
           --> weighting by ratio
           or
           --> weighting by sigma

AAP level:

 * Background subtraction
   (should be done preferably on SCP level to avoid color correction
    problems)
   --> Process
       --> Background Subtraction 
           --> another measurement
   (the background measurement has to be in the buffer, reduced
    in the same way.)

 * Display the SS-part of the spectrum
   --> Array --> Spectra --> Flux Density --> New

 * Load the SL-part of the spectrum
   --> Data --> Load (click on SL-Measurement, ok)

 * Overplot the SL-part of the spectrum
   --> Array --> Spectra --> Flux Density --> Overplot --> Synchronized