Index: trunk/ppImage/src/ppImageOptions.c
===================================================================
--- trunk/ppImage/src/ppImageOptions.c	(revision 17488)
+++ trunk/ppImage/src/ppImageOptions.c	(revision 17685)
@@ -180,6 +180,6 @@
                                                    overscanStats, boxcar, gauss);
 
-	options->overscan->constant = psMetadataLookupBool(NULL, recipe, "OVERSCAN.CONSTANT");
-	options->overscan->value = psMetadataLookupF32(NULL, recipe, "OVERSCAN.VALUE");
+        options->overscan->constant = psMetadataLookupBool(NULL, recipe, "OVERSCAN.CONSTANT");
+        options->overscan->value = psMetadataLookupF32(NULL, recipe, "OVERSCAN.VALUE");
 
         psFree(overscanStats);
@@ -257,7 +257,9 @@
 
     // even if not requested explicitly, if any of these are set, build an internal mask and weight:
-    if (options->doMask || options->doShutter || options->doFlat || options->doPhotom) {
+    if (options->doDark || options->doShutter || options->doFlat || options->doPhotom) {
         options->doMaskBuild = true;
         options->doWeightBuild = true;
+    } else if (options->doMask || options->doBias || options->doOverscan) {
+        options->doMaskBuild = true;
     }