Index: branches/eam_branches/psphot.stack.20100120/doc/stack.txt
===================================================================
--- branches/eam_branches/psphot.stack.20100120/doc/stack.txt	(revision 26642)
+++ branches/eam_branches/psphot.stack.20100120/doc/stack.txt	(revision 26643)
@@ -1,2 +1,27 @@
+
+20100120 : more stack processing mods:
+
+  there are a number of data collections generated during psphotReadout:
+
+  * detections (currently a structure containing multiple arrays)
+  * sources (a psArray)
+  * psf (the psf model structure)
+  
+  * new sources vs old sources:
+    there is a sequence on the second pass in which we need to distinguish the sources
+    from the first pass from those on the second pass:
+
+    - add noise (old sources only)
+    - find detections
+    - subtract noise (old sources only)
+    - generate sources (new detections only)
+    - source classifications (new sources only)
+    - guess models (new sources only)
+    - replace sources (old sources only)
+    - merge sources (new + old -> sources)
+
+    currently we are distiguishing the old vs new based on different arrays.
+    can we use the processing flags to distinguish the these cases and carry around 
+    only a single source list?
 
 20100107 : updates for stack processing