
raising bits : these functions may raise:

psphotSourceStats : BELOW_MOMENTS_SN | SKY_FAILURE | SKYVAR_FAILURE | BIG_RADIUS | MOMENTS_FAILURE

psphotBasicDeblend : BLEND 

psphotDeblendSatstars : BLEND 

psphotRoughClass : SATSTAR | SATURATED | DEFECT | PSFSTAR

psphotChoosePSF : can remove PSFSTAR from failed candidates

psphotGuessModels : BADPSF

psphotMergeSources : PSFSTAR | EXTERNAL 
  * note : this filters out 'bad' sources -- maybe too restrictive?
  
psphotFitSourcesLinearStack : LINEAR_FIT

psphotSourceSize : SIZE_SKIPPED | DEFECT | EXT_LIMIT | CR_LIMIT 

psphotApResid : AP_MAGS

psphotRadialAperturesByObject RADIAL_FLUX | EXTENDED_STATS

psphotExtendedSourceFits : EXTENDED_FIT

****

flags from psastro:

 OFF_CHIP | ON_GHOST | ON_GLINT | ON_SPIKE

