Index: trunk/Ohana/src/opihi/dvo/skycoverage.c
===================================================================
--- trunk/Ohana/src/opihi/dvo/skycoverage.c	(revision 31635)
+++ trunk/Ohana/src/opihi/dvo/skycoverage.c	(revision 32632)
@@ -202,5 +202,5 @@
 	V[ys*Nx + xs] = ShowDensity ?  0 : 2;
       } else {
-	V[ys*Nx + xs] = ShowDensity ? -1 : 0;
+	V[ys*Nx + xs] = ShowDensity ? NAN : 0;
       }
     }