Index: /branches/eam_branches/ipp-20150625/Ohana/src/libdvo/src/AstromOffsetMapOps.c
===================================================================
--- /branches/eam_branches/ipp-20150625/Ohana/src/libdvo/src/AstromOffsetMapOps.c	(revision 38714)
+++ /branches/eam_branches/ipp-20150625/Ohana/src/libdvo/src/AstromOffsetMapOps.c	(revision 38715)
@@ -405,6 +405,6 @@
     // data value & weight for this point
     if (!isfinite(f[i])) continue;
-    if (!isfinite(df[i])) continue;
-    if (df[i] == 0.0) continue;
+    if (df && !isfinite(df[i])) continue;
+    if (df && df[i] == 0.0) continue;
 
     // if (mask && (mask[i] & maskValue)) continue;
@@ -421,5 +421,5 @@
     int N = Nvalue[I];
     values[I][N] = f[i];
-    dvalues[I][N] = df[i];
+    dvalues[I][N] = df ? df[i] : 1.0;
     Nvalue[I] ++;
   }