Index: trunk/FACT++/www/viewer/index.html
===================================================================
--- trunk/FACT++/www/viewer/index.html	(revision 17806)
+++ trunk/FACT++/www/viewer/index.html	(revision 17807)
@@ -244,5 +244,6 @@
          </td>
          <td style="text-align:center;">
-            <input id="marker" type="checkbox" checked="true" onclick="onMarker();">Show pixel marker</input>
+            <input id="marker" type="checkbox" checked="true" onclick="refreshCameras();">Marker</input>&nbsp;&nbsp;
+            <input id="image" type="checkbox" onclick="refreshCameras();">Image</input>
             <!--Pixel value: 
             <input id="value" type="text" readonly="true"  value="0" style="text-align:right;width:100px"></input>-->
@@ -590,4 +591,14 @@
 survive changing files, events or pixel.
 
+<H3>What is the meaning of the image?</H3>
+The image is a representation of the first and second moment of the
+distribution of the pixel values. The first moment is the center-of-gravity
+of the distirbution, the major and minor axis represent the standard 
+deviation around the center-of-gravity (<i>width</I> and <i>length</I>). 
+The line represents an estimate for the distance of the center-of-gravity
+to the origin of the primary particle (<i>disp</i>). Due to the lack
+of more information, it is a very simple estimate using
+disp=1.42*(1-width/length).
+
 <H3>Why is loading the page so slow?</H3>
 The total contents of the javascript libraries is about 1MB which