Index: branches/czw_branch/20160809/psModules/src/astrom/pmAstrometryDistortion.c
===================================================================
--- branches/czw_branch/20160809/psModules/src/astrom/pmAstrometryDistortion.c	(revision 39723)
+++ branches/czw_branch/20160809/psModules/src/astrom/pmAstrometryDistortion.c	(revision 39754)
@@ -335,5 +335,7 @@
 
     psFree (fpa->fromTPA);
-    fpa->fromTPA = psPlaneTransformInvert(NULL, fpa->toTPA, *region, 50);
+    psPlaneTransform *myPT = psPlaneTransformAlloc(fpa->toTPA->x->nX+4, fpa->toTPA->x->nY+4);
+    fpa->fromTPA = psPlaneTransformInvert(myPT, fpa->toTPA, *region, 50);
+    psFree (myPT);
     psFree (region);
 
Index: branches/czw_branch/20160809/psModules/src/astrom/pmAstrometryWCS.c
===================================================================
--- branches/czw_branch/20160809/psModules/src/astrom/pmAstrometryWCS.c	(revision 39723)
+++ branches/czw_branch/20160809/psModules/src/astrom/pmAstrometryWCS.c	(revision 39754)
@@ -691,5 +691,7 @@
     // the region defines the FPA pixels covered by the tranformation
     psFree (fpa->fromTPA);
-    fpa->fromTPA = psPlaneTransformInvert(NULL, fpa->toTPA, region, 50);
+    psPlaneTransform *myPT = psPlaneTransformAlloc(fpa->toTPA->x->nX+4, fpa->toTPA->x->nY+4);
+    fpa->fromTPA = psPlaneTransformInvert(myPT, fpa->toTPA, region, 50);
+    psFree (myPT);
     return true;
 }