Index: /trunk/FACT++/www/viewer/index.html
===================================================================
--- /trunk/FACT++/www/viewer/index.html	(revision 17816)
+++ /trunk/FACT++/www/viewer/index.html	(revision 17817)
@@ -134,22 +134,26 @@
    <input id="submit"  type="button" onclick="onSubmit();" value="Submit"></input>
    <span style="float:right;white-space:nowrap;">
-      Cal:
-      <input id="calibrated" type="checkbox" onclick="onSubmit();"></input>
-      Run: 
+      MC
+      <input id="montecarlo" style="margin-left:0px;margin-right:5px;" type="checkbox" onclick="onSubmit();" disabled="true"></input>
+      DRS
+      <input id="drsfile" style="margin-left:0px;margin-right:5px;" type="checkbox" onclick="onSubmit();"></input>
+      Cal
+      <input id="calibrated" style="margin-left:0px;margin-right:5px;" type="checkbox" onclick="onSubmit();"></input>
+      Run 
       <input id="file" style="width:100px"></input>
    </span>
    &nbsp;
    <span style="white-space:nowrap">
-      Evt: 
+      Evt 
       <input id="event" style="text-align:right;" type="number" onchange="onEvent();"  value="0" min="0" max="0"    step="1"></input>/<span id="numevents">---</span>
    </span>
    &nbsp;
    <span style="white-space:nowrap">
-      Pix: 
+      Pix 
       <input id="pixel" style="text-align:right;width:50px;" type="number" onchange="onPixel();"  value="0" min="0" max="1439" step="1"></input>
    </span>
    &nbsp;
    <span style="white-space:nowrap">
-      CBPX:
+      CBPX
       <input id="cbpx-c" style="text-align:right;width:30px;" type="number" onchange="onCBPX();"  value="1" min="0" max="3" step="1"></input>
       <input id="cbpx-b" style="text-align:right;width:30px;" type="number" onchange="onCBPX();"  value="0" min="0" max="9" step="1"></input>
@@ -547,4 +551,22 @@
 it fom the pull down.
 
+<H3>What is the meaning of the DRS and Cal checkboxes?</H3>
+For some files, files which contain calibrated data are available. 
+This means that the DRS calibration (offset (1024), gain and offset
+(roi)) has been applied. Enabling the checkbox will show this data
+instead of the raw data. Note that the precision is limited to 0.1mV.
+In some cases files were taken to deduce this calibration constants
+(DRS files). This is done in four steps: offset, gain, offset (1024),
+offset (roi). These steps are called 0, 1, 2 and 2 respectively. If the
+checkbox Drs is enabled, the corresponding calibration constants as
+stored in the .drs.fits file, are shown, which is
+<I>BaselineMean</I> [0], <I>GainMean</I> [1] and <I>TriggerOffsetMean</I> [2].
+
+<H3>What is the meaning of the MC checkbox?</h3>
+Currently, it is only to indicate whether the chosen file
+is a Monte Carlo file or not. At the moment, all available
+Monte Carlo file have a four-digit <I>year</I> starting with
+a 0.
+
 <H3>How to change the displayed pixel?</H3>
 Enter the pixel number on the corresponding field or its hwardware