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PIA V7.0 - 20/02/98
========

As always, but specially in this case, the following list is not containing all
changes performed to PIA (the special case is given by the fact, that there are
173 new and changed files in the source) but only the most important ones. The 
updated User's Manual corresponds to this new version, giving more details.  


CONFIGURATION:
--------------

* PIA V7.0 runs only under IDL 5. This was decided in the first PIA Users Group
meeting, on the basis of the answers to a questionnaire sent to registered PIA
users several months ago. 

* PIA V7.0 does not support VMS anymore. This is also an outcome of the 
questionnaire mentioned above. 
  
  
HELP & DOCUMENTATION:
---------------------

* PIA's homepage (http://isowww.estec.esa.nl/manuals/PHT/pia/) mirrored at the 
national PHT-Data Center (http://www.mpia-hd.mpg.de/MPIA/Projects/ISO/index.html) 
at MPIA (allowing also for retrieving).

* Update of the PIA User's Manual (V7.0) is done and it is issued with
this version. We anticipate the issue of a LaTeX version of the manual also 
within few weeks.  

 
PROCESSING:
-----------


* Dark Current orbital dependences: have been established and put into new Cal G
  files (PPDARKC, PC1DARKC, PC2DARKC, PSLDARKC) which replace the obsolete 
  Cal G file PDARKCUR. In the new files the default dark currents are given in 
  bins of ISO orbital positions. Within PIA different interpolations can be used
  for subtracting dark current, per signal (or signal per chopper plateau), per
  raster point, per measurement or per AOT (default used by the Pipeline V7.0)

* Default Responsivities: by several detectors a dependence on the orbital position
  has been also found. New Cal G files for default response per detector have been 
  produced for P and C detectors (PPRESP, PC1RESP, PC2RESP), which replace the 
  obsolete file PRESPONS. PIA offers again here different interpolations, although
  limited to a value per measurement or per AOT (latter is pipeline default).

* The reset interval correction, implemented in PIA V6.4, but not reachable until
  now by the external version, is now fully operable. Furthermore, it should be 
  always applied, since all calibration files depending on this effect, have been 
  derived using this correction. 

* A chopper frequency correction has been implemented for background subtracted
  chopped measurements, which corrects for signal deficits caused by different
  chopping frequencies. The correction factors are taken from new Cal G files 
  (P#CHOPCOR, # being either 'P', or 'C1' or 'C2')

* A new deglitching processing has been implemented on the ERD levels, based on 
  a two thresholds algorithm. In addition to a higher efficiency it offers the 
  possibility of deglitching also short ramps, not possible with the old "Ramps
  deglitching". The use of the different deglitching methods can be alternative 
  or even complementary. (see also under Graphical I/O)

* New Cal G files containing the solid angles Omega per filter and aperture, 
  aperture dimensions, and pixel offsets relative to center of array for the 
  C detectors case have being implemented, following the first results of deep
  studies on beam profiles.
  
* Limits indicating the validity range of the FCS power tables have being added
  to the calibration files. These limits are used to issue a warning if a 
  responsivity is derived using an FCS measurement using an electrical power 
  lying outside the limits. Additionally, if this happens during AOT/BATCH
  processing, default responsivities are automatically taken and this is quoted
  to the user.     

* Sparse map handling - Raster map handling - Meas. sequence handling: The 
  production of maps out of sparse observations (but also out of any
  observations, not necessarily AOT-like connected ones) is implemented (see
  Graphical I/F). 

* PHT-S data can be also processed to maps, with the possibility of using data
  per pixel or per user defined wavelength region.
  
* Extended (and with better resolution) tables for color corrections assuming 
  1/nu or 1/nu^2 spectrae. The temperature region is now the same as for a 
  blackbody spectrum. All CC tables are now contained in FITS files, which are
  delivered together with PIA.  
   
* Checks for wrong raster point ID's (set to [0,0]) are performed and the values
  corrected while reducing data from ERD to SRD.

GRAPHICAL I/F:
--------------

* The new IDL5 feature of no blocking widgets is used, so that while PIA is 
  running, you have full access to IDL (from the IDL prompt) including to all 
  PIA buffers and routines. 

* The main I/F for general AOT ("batch") processing includes now the choices of 
  all the corrections desired behind choosable buttons (per level). All the 
  corrections which use variable parameters can be customized from the same I/F.
  
* Limits can be given for number of elements in plots and zoomed plots. This 
  allows for higher graphical speed. If this option is taken, a warning is 
  issued telling you that the plots you are looking at are not complete, unless
  such a warning is already present on the screen (or iconized, of course). 
  
* Main I/F's do exist now for the AAP level, controlling the access to all its
  variables, and including correction and processing for this level. Here is 
  the possibility given of concatenating measurements for producing eg sparse 
  maps or mosaicing. 
  
* Testing I/F for the new implemented "two threshold" algorithm for deglitching,
  including statistics recording in the same fashion as for the ramp
  deglitching.
   

I/O & Calibration Files:
------------------------

* A lot of new Cal G files required new read routines, new data areas for 
  maintaining this data (and changes in the routines handling with): 

	- P*RESP (orbital position dependent responsivities)
	- P*DARK (orbital position dependent dark currents)
	- P*CHOPCOR (corrections for chopper frequency dependent signal loses)
	- P*OMEGA (solid angles)
	- PCC_*  (colour correction tables [BB, 1/nu, 1/nu^2, PowerLaw])
	
  The P*RESP for P3, C100 and C200 contain a time dependance, due to application
  of recuring proceeding in the middle of the orbit from Rev. 150 on. 
  
 
Drift handling:
---------------

* New constants derived and implemented for P3, C100 and C200 "single
  exponential function"


Calibration menues:
-------------------

* New menues for accessing and visualising the orbital position dependent 
  default responses and dark currents.

* Menu for color correction tables changed according to extended corrections. 


Bugs fixed:
-----------

* Initialisation of triangular chopped mode for transients fitting. 
  


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