Index: trunk/Ohana/src/opihi/cmd.data/wd.c
===================================================================
--- trunk/Ohana/src/opihi/cmd.data/wd.c	(revision 18279)
+++ trunk/Ohana/src/opihi/cmd.data/wd.c	(revision 20652)
@@ -82,5 +82,6 @@
 
   if (temp_header.Naxes) {
-    gfits_convert_format (&temp_header, &temp_matrix, outBitpix, outScale, outZero, outUnsign);
+    // the inBlank value probably does not matter: temp_matrix is float, so nan is used
+    gfits_convert_format (&temp_header, &temp_matrix, outBitpix, outScale, outZero, 0xffff, outUnsign);
   } else {
     gfits_modify (&temp_header, "BITPIX", "%d", 1, outBitpix);