Index: /branches/eam_branch_20080511/ppSim/src/ppSimLoadSpots.c
===================================================================
--- /branches/eam_branch_20080511/ppSim/src/ppSimLoadSpots.c	(revision 17960)
+++ /branches/eam_branch_20080511/ppSim/src/ppSimLoadSpots.c	(revision 17961)
@@ -30,4 +30,9 @@
     float dec0    = psMetadataLookupF32(NULL, recipe, "DEC");       // Boresight Dec (radians)
     float scale   = psMetadataLookupF32(NULL, recipe, "PIXEL.SCALE") * M_PI / 3600.0 / 180.0; // Plate scale (radians/pixel)
+
+    if (isnan(ra0) || isnan(dec0)) {
+        psError(PS_ERR_UNKNOWN, false, "image boresite coords not defined.");
+	return false;
+    }
 
     char *catdir = psMetadataLookupStr(NULL, recipe, "FORCED.CATDIR");