Index: trunk/tools/czartool/Czarplot.pm
===================================================================
--- trunk/tools/czartool/Czarplot.pm	(revision 28775)
+++ trunk/tools/czartool/Czarplot.pm	(revision 28776)
@@ -174,15 +174,20 @@
     my $divX = $timeDiff/4;
 
-    # if less than a couple of hours data plotted, show 30 mins tics
+    # if less than a couple of hour's data plotted, show 30 mins tics
     if ($timeDiff < 7200) {
         $timeFormat = "%H:%M";
         $divX = 1800;
     }
-    # if less than one days data plotted, show hourly tics
+    # if less than half a day's data plotted, show hourly tics
+    elsif ($timeDiff < 43200) {
+        $timeFormat = "%H:%M";
+        $divX = 3600;
+    }
+    # if less than one day's data plotted, show 2 hourly tics
     elsif ($timeDiff < 86400) {
         $timeFormat = "%H:%M";
-        $divX = 3600;
-    }
-    # if more than one days data plotted, show daisy tics
+        $divX = 7200;
+    }
+    # if more than one day's data plotted, show daily tics
     else {