Index: trunk/ippScripts/scripts/stack_skycell.pl
===================================================================
--- trunk/ippScripts/scripts/stack_skycell.pl	(revision 19932)
+++ trunk/ippScripts/scripts/stack_skycell.pl	(revision 19938)
@@ -267,5 +267,5 @@
             $command .= " -uri $outputName -path_base $outroot";
             $command .= " -hostname $host" if defined $host;
-            $command .= (" -dtime_script " . (($mjd_start - DateTime->now->mjd) * 86400));
+            $command .= (" -dtime_script " . ((DateTime->now->mjd - $mjd_start) * 86400));
         } else {
             $mode = "-updaterun -state full";
@@ -298,5 +298,5 @@
             $command .= " -addsumskyfile";
             $command .= " -hostname $host" if defined $host;
-            $command .= (" -dtime_script " . (($mjd_start - DateTime->now->mjd) * 86400));
+            $command .= (" -dtime_script " . ((DateTime->now->mjd - $mjd_start) * 86400));
         } else {
             $command .= " -updatesumskyfile";