Index: trunk/psModules/src/objects/pmPCM_MinimizeChisq.c
===================================================================
--- trunk/psModules/src/objects/pmPCM_MinimizeChisq.c	(revision 29012)
+++ trunk/psModules/src/objects/pmPCM_MinimizeChisq.c	(revision 32347)
@@ -45,4 +45,5 @@
 # define USE_FFT 1
 # define PRE_CONVOLVE 1
+# define TESTCOPY 0
 
 bool pmPCM_MinimizeChisq (
@@ -93,5 +94,9 @@
 	psFree (pcm->psfFFT);
     }
-    pcm->psfFFT = psImageConvolveKernelInit(pcm->modelFlux, pcm->psf);
+# if (!TESTCOPY)
+    if (!pcm->use1Dgauss) {
+	pcm->psfFFT = psImageConvolveKernelInit(pcm->modelFlux, pcm->psf);
+    }
+# endif
 # endif    
 
@@ -285,6 +290,6 @@
 
             // Convert i/j to image space:
-            coord->data.F32[0] = (psF32) (j + source->pixels->col0);
-            coord->data.F32[1] = (psF32) (i + source->pixels->row0);
+            coord->data.F32[0] = (psF32) (j + 0.5 + source->pixels->col0);
+            coord->data.F32[1] = (psF32) (i + 0.5 + source->pixels->row0);
 
             pcm->modelFlux->data.F32[i][j] = pcm->modelConv->modelFunc (deriv, params, coord);
@@ -309,5 +314,20 @@
 # if (PRE_CONVOLVE)
     // convolve model image and derivative images with pre-convolved kernel
-    psImageConvolveKernel (pcm->modelConvFlux, pcm->modelFlux, NULL, 0, pcm->psfFFT);
+
+// XXX for a test, just copy, rather than convolve
+# if (TESTCOPY)
+    psImageCopy (pcm->modelConvFlux, pcm->modelFlux, pcm->modelFlux->type.type);
+# else
+    if (pcm->use1Dgauss) {
+	// do not use the threaded, mask-aware version of this code (psImageSmoothMaskPixelsThread):
+	// * the model flux is not masked
+	// * threading takes place above this level
+	pcm->modelConvFlux = psImageCopy (pcm->modelConvFlux, pcm->modelFlux, pcm->modelFlux->type.type);
+	psImageSmooth (pcm->modelConvFlux, pcm->sigma, pcm->nsigma);
+    } else {
+	psImageConvolveKernel (pcm->modelConvFlux, pcm->modelFlux, NULL, 0, pcm->psfFFT);
+    }
+# endif
+
     for (int n = 0; n < pcm->dmodelsFlux->n; n++) {
         if (pcm->dmodelsFlux->data[n] == NULL) continue;
@@ -315,5 +335,17 @@
         psImage *dmodel = pcm->dmodelsFlux->data[n];
         psImage *dmodelConv = pcm->dmodelsConvFlux->data[n];
-        psImageConvolveKernel (dmodelConv, dmodel, NULL, 0, pcm->psfFFT);
+# if (TESTCOPY)
+	psImageCopy (dmodelConv, dmodel, dmodel->type.type);
+# else
+	if (pcm->use1Dgauss) {
+	    // do not use the threaded, mask-aware version of this code (psImageSmoothMaskPixelsThread):
+	    // * the model flux is not masked
+	    // * threading takes place above this level
+	    dmodelConv = psImageCopy (dmodelConv, dmodel, dmodel->type.type);
+	    psImageSmooth (dmodelConv, pcm->sigma, pcm->nsigma);
+	} else {
+	    psImageConvolveKernel (dmodelConv, dmodel, NULL, 0, pcm->psfFFT);
+	}
+# endif
     }
 # else
@@ -325,5 +357,14 @@
         psImage *dmodel = pcm->dmodelsFlux->data[n];
         psImage *dmodelConv = pcm->dmodelsConvFlux->data[n];
-        psImageConvolveFFT (dmodelConv, dmodel, NULL, 0, pcm->psf);
+
+	if (pcm->use1Dgauss) {
+	    // do not use the threaded, mask-aware version of this code (psImageSmoothMaskPixelsThread):
+	    // * the model flux is not masked
+	    // * threading takes place above this level
+	    dmodelConv = psImageCopy (dmodelConv, dmodel, dmodel->type.type);
+	    psImageSmooth (dmodelConv, pcm->sigma, pcm->nsigma);
+	} else {
+	    psImageConvolveFFT (dmodelConv, dmodel, NULL, 0, pcm->psf);
+	}
     }
 # endif // PRE-CONVOLVE