Index: /trunk/psastro/src/psastroAstromGuess.c
===================================================================
--- /trunk/psastro/src/psastroAstromGuess.c	(revision 12707)
+++ /trunk/psastro/src/psastroAstromGuess.c	(revision 12708)
@@ -62,5 +62,5 @@
     while ((chip = pmFPAviewNextChip (view, fpa, 1)) != NULL) {
         psTrace ("psastro", 4, "Chip %d: %x %x\n", view->chip, chip->file_exists, chip->process);
-        if (!chip->process || !chip->file_exists) { continue; }
+        if (!chip->process || !chip->file_exists || !chip->data_exists) { continue; }
 
         // read WCS data from the corresponding header