Index: /branches/eam_branches/ipp-20130904/psModules/src/objects/pmPCM_MinimizeChisq.c
===================================================================
--- /branches/eam_branches/ipp-20130904/psModules/src/objects/pmPCM_MinimizeChisq.c	(revision 36239)
+++ /branches/eam_branches/ipp-20130904/psModules/src/objects/pmPCM_MinimizeChisq.c	(revision 36240)
@@ -580,5 +580,5 @@
 
 	    // XXXX note this point here:::
-            float yweight = 1.0 / source->variance->data.F32[i][j];
+            float yweight = pcm->poissonErrors ? 1.0 / source->variance->data.F32[i][j] : 1.0;
             float delta = ymodel - source->pixels->data.F32[i][j];
 
Index: /branches/eam_branches/ipp-20130904/psModules/src/objects/pmPCMdata.c
===================================================================
--- /branches/eam_branches/ipp-20130904/psModules/src/objects/pmPCMdata.c	(revision 36239)
+++ /branches/eam_branches/ipp-20130904/psModules/src/objects/pmPCMdata.c	(revision 36240)
@@ -95,4 +95,6 @@
     pcm->nDOF = 0;
 
+    pcm->poissonErrors = true;
+
     // full convolution with the PSF is expensive.  if we have to save time, we can do a 1D
     // convolution with a Gaussian approximation to the kernel
@@ -365,4 +367,6 @@
     pcm->modelConv = psMemIncrRefCounter(model);
     pcm->constraint = constraint;
+
+    pcm->poissonErrors = fitOpions->poissonErrors;
 
     pcm->nPix = nPix;
Index: /branches/eam_branches/ipp-20130904/psModules/src/objects/pmPCMdata.h
===================================================================
--- /branches/eam_branches/ipp-20130904/psModules/src/objects/pmPCMdata.h	(revision 36239)
+++ /branches/eam_branches/ipp-20130904/psModules/src/objects/pmPCMdata.h	(revision 36240)
@@ -35,4 +35,6 @@
     int nPar;
     int nDOF;
+
+    bool poissonErrors;
 
     bool use1Dgauss;