Index: /trunk/psModules/src/objects/models/pmModel_QGAUSS.c
===================================================================
--- /trunk/psModules/src/objects/models/pmModel_QGAUSS.c	(revision 11300)
+++ /trunk/psModules/src/objects/models/pmModel_QGAUSS.c	(revision 11301)
@@ -348,4 +348,13 @@
     out[PM_PAR_SXY] = pmPSF_SXYtoModel (out);
 
+    // apply the model limits here: this truncates excessive extrapolation
+    for (int i = 0; i < psf->params_NEW->n; i++) {
+        // apply the limits to all components or just the psf-model parameters?
+        if (psf->params_NEW->data[i] == NULL)
+            continue;
+        PM_MODEL_LIMITS (PS_MINIMIZE_PARAM_MIN, i, out, NULL);
+        PM_MODEL_LIMITS (PS_MINIMIZE_PARAM_MAX, i, out, NULL);
+    }
+
     return(true);
 }