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== ippToPsps for SAS V9 ==


This the list of changes, ingredients, and processing of sas_v9.

=== ipp changes ===

  * best qf_perfect, best sg_sep reported for dvo averages
  * does the right thing for nx=0 - mags are null
  * nigel's "goofy mags" due to dvo having duplicates - should be fixed both in dvo and in ipptopsps
  * Better modeling and subtraction of flux from very bright stars (subtract a smoothed radial profile) -- reduces number of false detections
  * do not allow negative fluxes for real detected objects in linear flux fit - improves measurements of nearby sources
  * use a mask to prevent detections on 2nd pass within 1" of detections from 1st pass
  * Changes to psphotStack object matching- reduces spurious sources
   * Require object be detected in 2 bands before creating sources for forced photometry (matched sources)...
   * ... Except if only detection is in y band perform forced photometry in
     all bands.
   * Drop matched sources for which aperture flux is not finite (This usually
     happens when the pixels in the matched band are totally masked)
  * Insure that NAN pixels in image and variance images are masked. This avoids several crashes that prevented some static sky analysis from completing for some skycells.
 * Better error handling in Kron radius measurements. This reduces spurious large values.
 * When psf matching fails for an input continue with the psphotStack analysis skipping the radial aperture measurements for the matched images in that band.
 * Perform psphotStack even if stacks are available for less than five filters in a given skycell.
 * Fix N_FRAMES measurement which was getting lost in the skycell calibration process.
 * In DVO correct an error in zero point application to the object level flux measurments
=== dvo ===

The new dvo is called SAS.20120905, located /data/ipp005.0/gpc1/catdirs/SAS/20120901  (yes, different dates, that is a typo from when Heather queued)
 
Ingredients for the dvo:
  * cam stage label = 'SAS_v8', 620 entries
  * skycal stage label = 'SAS_v9', this is rerunning psphotstack (ie, staticsky and skycal stage) on the SAS_v8 pixels
  * dvo type is PS1_V4 with modifications (ie, the PS1_V4 database from before, SAS.20120801, is not compatible)

Commands used to 'spiff' the dvo (trunk from 2012-09-05):
  {{{
 relphot -averages -reset -update -boundary-tree ~ipp/RINGS.V3.tree.fits -D CAMERA gpc1 -D CATDIR /data/ipp005.0/gpc1/catdirs/SAS/20120901
 relastro -update-objects -reset -update -D CAMERA gpc1 -D CATDIR /data/ipp005.0/gpc1/catdirs/SAS/20120901
 }}}
 
Some more fixes were added, at which point I was instructed to update Ohana/src/relphot and to rerun the command (from 2012-09-14)
{{{
 relphot -averages -reset -update -boundary-tree ~ipp/RINGS.V3.tree.fits -D CAMERA gpc1 -D CATDIR /data/ipp005.0/gpc1/catdirs/SAS/20120901
}}}

Heather looked at the dvo: it looks reasonable.

=== ippToPsps ===

Lots of changes to ippToPsps this time around:

Object Tables
 * [x]flags have been added
 * extra has been added - this is now the best qf_perfect
 * sgsep has been added
 * raErr has been added
 * decErr has been added
 * x20pct/x80pct now correctly defaults to -999 for NULL
 * xStackKronMag now has correct mags (not offset by 17.8)
 
Stack Detection Full
 * kronrad has been added, with value of MOMENTS_R1*2.5
 * nigel's "goofy mags" due to dvo having duplicates - should be fixed both in dvo and in ipptopsps
 * infoFlags is now FLAGS2 << 32 | FLAGS to be consistent with other tables


===  problems ===
 * default config had changed.  It's actually not used, but it complained since some parameters were missing. Ugh.
 * ipptopsps needs to know about the changes to the dvo to properly grab it. This was sorted out by checking out the trunk (ipptrunk-20120913), compiling it, and telling ipptopsps to use that psconfig instead of the default ipp tag.