Index: /trunk/MagicSoft/Mars/msignal/MExtractor.cc
===================================================================
--- /trunk/MagicSoft/Mars/msignal/MExtractor.cc	(revision 3880)
+++ /trunk/MagicSoft/Mars/msignal/MExtractor.cc	(revision 3881)
@@ -102,4 +102,5 @@
 // The PreProcess searches for the following input containers:
 //  - MRawEvtData
+//  - MRawRunHeader
 //  - MPedestalCam
 //
@@ -145,4 +146,20 @@
 }
 
+// --------------------------------------------------------------------------
+//
+// The ReInit searches for:
+// -  MRawRunHeader::GetNumSamplesHiGain()
+// -  MRawRunHeader::GetNumSamplesLoGain()
+//
+// In case that the variables fHiGainLast and fLoGainLast are smaller than 
+// the even part of the number of samples obtained from the run header, a
+// warning is given an the range is set back accordingly. A call to:  
+// - SetRange(fHiGainFirst, fHiGainLast-diff, fLoGainFirst, fLoGainLast) or 
+// - SetRange(fHiGainFirst, fHiGainLast, fLoGainFirst, fLoGainLast-diff) 
+// is performed in that case. The variable diff means here the difference 
+// between the requested range (fHiGainLast) and the available one. Note that 
+// the functions SetRange() are mostly overloaded and perform more checks, 
+// modifying the ranges again, if necessary.
+//
 Bool_t MExtractor::ReInit(MParList *pList)
 {