Changeset 17709

Timestamp:

May 16, 2008, 6:37:20 AM (18 years ago)

Author:

eugene

Message:

adding functions to support photometry

Location:

branches/eam_branch_20080511/ppSim

Files:

• notes.txt (modified) (1 diff)
• src/ppSimLoadForceSources.c (added)
• src/ppSimPhotomReadout.c (added)

branches/eam_branch_20080511/ppSim/notes.txt

@@ -1 +1 @@
 
-2008.05.14 
+2008.05.15
 
-  ppSim needs some work to be a bit more realistic.  It currently does
-  not do the correct thing for generating flats or shutter
-  corrections.  It is only applying them to the background sky model.
-  It is not applying them to the stellar flux.  Also, for adding
-  sources on top of existing images, it needs to apply the Poisson
-  stats to the generated stars and then add the pixel values to the
-  input image.  currently, it is placing them directly in the input
-  image.
+  For fake and force photometry, we need to load the known existing
+  sources, then perform a complete linear fit solution to the complete
+  set of both real (known) sources plus the fake and/or forced
+  photometry positions (as PSFs).  The fake and forced photometry
+  positions need to be measured independently.  This provides the real
+  photometry for these sources ** in the presence of the other real
+  sources **.  In order to test the detectability of the fake sources
+  (or the forced sources, for that matter), we need to generate the
+  smoothed detection image, and determine the peak value at the
+  positions of the sources.  
+
+  ppSimPhotomReadout outline:
+
+  * we have three source lists (loaded before the function is called):
+    * realSources : these are loaded from a CMF-style file (or equiv)
+    * fakeSources : these are defined internally, and need a link from
+                    the input fake source to the measured fake source
+    * forceSources : these are loaded from a DVO database via getstar
+
+  * we require a supplied PSF
+
+  * need to subtract the background (before or after subtracting the
+    sources?)
+
+  * subtract the real sources
+  * model the background
+  * build the detection image
+  * measure the detectability of the fake and force sources
+  * replace the real sources
+
+  * merge real + fake sources
+  * linear fit to merged source list
+  * replace the sources (make 'no-subtract' option?)
+
+  * merge real + forced sources
+  * linear fit to merged source list
+  * replace the sources (make 'no-subtract' option?)