diff --git a/Modules/DiffusionImaging/IODataStructures/DiffusionWeightedImages/mitkDiffusionImage.h b/Modules/DiffusionImaging/IODataStructures/DiffusionWeightedImages/mitkDiffusionImage.h
index 7ccfb4b56c..a7883718d9 100644
--- a/Modules/DiffusionImaging/IODataStructures/DiffusionWeightedImages/mitkDiffusionImage.h
+++ b/Modules/DiffusionImaging/IODataStructures/DiffusionWeightedImages/mitkDiffusionImage.h
@@ -1,140 +1,124 @@
 /*===================================================================
 
 The Medical Imaging Interaction Toolkit (MITK)
 
 Copyright (c) German Cancer Research Center, 
 Division of Medical and Biological Informatics.
 All rights reserved.
 
 This software is distributed WITHOUT ANY WARRANTY; without 
 even the implied warranty of MERCHANTABILITY or FITNESS FOR 
 A PARTICULAR PURPOSE.
 
 See LICENSE.txt or http://www.mitk.org for details.
 
 ===================================================================*/
 
 
 #ifndef __mitkDiffusionImage__h
 #define __mitkDiffusionImage__h
 
 #include "mitkImage.h"
 #include "itkVectorImage.h"
 #include "itkVectorImageToImageAdaptor.h"
 #include <iomanip>
 #include <itkCommand.h>
 
 namespace mitk
 {
 
 /**
   * \brief this class encapsulates diffusion volumes (vectorimages not
   * yet supported by mitkImage)
   */
 template<class TPixelType>
 class DiffusionImage : public Image
 {
 
 public:
   typedef TPixelType PixelType;
   typedef typename itk::VectorImage<TPixelType, 3>
   ImageType;
   typedef vnl_vector_fixed< double, 3 >       GradientDirectionType;
   typedef itk::VectorContainer< unsigned int,
   GradientDirectionType >                   GradientDirectionContainerType;
   typedef itk::VectorImageToImageAdaptor< TPixelType, 3 >
   AdaptorType;
   typedef vnl_matrix_fixed< double, 3, 3 >      MeasurementFrameType;
 
   // BValue Map
   // key   := b-Value
   // value := indicesVector (containing corresponding gradient directions for a b-Value-Shell
   typedef std::vector< unsigned int > IndicesVector;
   typedef std::map< double , IndicesVector >  BValueMap;
 
   mitkClassMacro( DiffusionImage, Image );
   itkNewMacro(Self);
 
 
   void AverageRedundantGradients(double precision);
 
   GradientDirectionContainerType::Pointer CalcAveragedDirectionSet(double precision, GradientDirectionContainerType::Pointer directions);
 
   void CorrectDKFZBrokenGradientScheme(double precision);
 
   typename ImageType::Pointer GetVectorImage() { return m_VectorImage; }
   void SetVectorImage(typename ImageType::Pointer image ) { this->m_VectorImage = image; }
 
   void InitializeFromVectorImage();
   void SetDisplayIndexForRendering(int displayIndex);
 
   GradientDirectionContainerType::Pointer GetDirections() { return m_Directions; }
   void SetDirections( GradientDirectionContainerType::Pointer directions ) { this->m_Directions = directions; }
   void SetDirections(const std::vector<itk::Vector<double,3> > directions);
 
   GradientDirectionContainerType::Pointer GetOriginalDirections()  { return m_OriginalDirections; }
   void SetOriginalDirections( GradientDirectionContainerType::Pointer directions )   { this->m_OriginalDirections = directions; this->ApplyMeasurementFrame(); }
   void SetOriginalDirections(const std::vector<itk::Vector<double,3> > directions);
 
   MeasurementFrameType GetMeasurementFrame()  { return m_MeasurementFrame; }
   void SetMeasurementFrame( MeasurementFrameType mFrame )  { this->m_MeasurementFrame = mFrame; this->ApplyMeasurementFrame(); }
 
   bool AreAlike(GradientDirectionType g1, GradientDirectionType g2, double precision);
   int GetNumDirections();
   int GetNumB0();
 
   float GetB_Value(int i);
   bool IsMultiBval();
   void UpdateBValueList();
 
-  void AddObserver() {
-    // Add Observer for m_Directions
-    typedef DiffusionImage< TPixelType > Self;
-
-    typedef itk::SimpleMemberCommand< Self >  DCCommand ;
-
-    typename DCCommand::Pointer command = DCCommand::New();
-
-    command->SetCallbackFunction(this, &Self::UpdateBValueList);
-
-    m_DirectionsObserverTag = m_Directions->AddObserver(itk::ModifiedEvent(), command);
-  }
-
-  void RemoveObserver() {
-    // Remove Observer for m_Directions
-    m_Directions->RemoveObserver(m_DirectionsObserverTag );
-  }
-
   IndicesVector GetB0Indices();
 
   itkGetMacro(B_Value, float);
   itkSetMacro(B_Value, float);
 
   BValueMap GetB_ValueMap(){ return m_B_ValueMap; }
 
+  void AddDirectionsContainerObserver();
+  void RemoveDirectionsContainerObserver();
 
 protected:
   DiffusionImage();
   virtual ~DiffusionImage();
 
   void ApplyMeasurementFrame();
 
   typename ImageType::Pointer               m_VectorImage;
   GradientDirectionContainerType::Pointer   m_Directions;
   GradientDirectionContainerType::Pointer   m_OriginalDirections;
   float                                     m_B_Value;
   typename AdaptorType::Pointer             m_VectorImageAdaptor;
   int                                       m_DisplayIndex;
   MeasurementFrameType                      m_MeasurementFrame;
   BValueMap                                 m_B_ValueMap;
 
 
 
   unsigned long    m_DirectionsObserverTag;
 };
 
 } // namespace mitk
 
 #include "mitkDiffusionImage.txx"
 
 #endif /* __mitkDiffusionImage__h */
diff --git a/Modules/DiffusionImaging/IODataStructures/DiffusionWeightedImages/mitkDiffusionImage.txx b/Modules/DiffusionImaging/IODataStructures/DiffusionWeightedImages/mitkDiffusionImage.txx
index c882c09ce8..fdccc5023f 100644
--- a/Modules/DiffusionImaging/IODataStructures/DiffusionWeightedImages/mitkDiffusionImage.txx
+++ b/Modules/DiffusionImaging/IODataStructures/DiffusionWeightedImages/mitkDiffusionImage.txx
@@ -1,477 +1,512 @@
 /*===================================================================
 
 The Medical Imaging Interaction Toolkit (MITK)
 
 Copyright (c) German Cancer Research Center, 
 Division of Medical and Biological Informatics.
 All rights reserved.
 
 This software is distributed WITHOUT ANY WARRANTY; without 
 even the implied warranty of MERCHANTABILITY or FITNESS FOR 
 A PARTICULAR PURPOSE.
 
 See LICENSE.txt or http://www.mitk.org for details.
 
 ===================================================================*/
 
 #include "itkImageRegionIterator.h"
 #include "itkImageRegionConstIterator.h"
 #include "mitkImageCast.h"
 
 template<typename TPixelType>
 mitk::DiffusionImage<TPixelType>::DiffusionImage()
   : m_VectorImage(0), m_Directions(0), m_OriginalDirections(0), m_B_Value(-1.0), m_VectorImageAdaptor(0)
 {
   MeasurementFrameType mf;
   for(int i=0; i<3; i++)
     for(int j=0; j<3; j++)
       mf[i][j] = 0;
   for(int i=0; i<3; i++)
     mf[i][i] = 1;
   m_MeasurementFrame = mf;
-
-  AddObserver();
 }
 
 template<typename TPixelType>
 mitk::DiffusionImage<TPixelType>::~DiffusionImage()
 {
-  RemoveObserver();
+  // Remove Observer for m_Directions
+  m_Directions->RemoveObserver(m_DirectionsObserverTag );
 }
 
 template<typename TPixelType>
 void mitk::DiffusionImage<TPixelType>
 ::InitializeFromVectorImage()
 {
   if(!m_VectorImage || !m_Directions || m_B_Value==-1.0)
   {
     MITK_INFO << "DiffusionImage could not be initialized. Set all members first!" << std::endl;
     return;
   }
 
   // find bzero index
   int firstZeroIndex = -1;
   for(GradientDirectionContainerType::ConstIterator it = m_Directions->Begin();
       it != m_Directions->End(); ++it)
   {
     firstZeroIndex++;
     GradientDirectionType g = it.Value();
     if(g[0] == 0 && g[1] == 0 && g[2] == 0 )
       break;
   }
 
   typedef itk::Image<TPixelType,3> ImgType;
   typename ImgType::Pointer img = ImgType::New();
   img->SetSpacing( m_VectorImage->GetSpacing() );   // Set the image spacing
   img->SetOrigin( m_VectorImage->GetOrigin() );     // Set the image origin
   img->SetDirection( m_VectorImage->GetDirection() );  // Set the image direction
   img->SetLargestPossibleRegion( m_VectorImage->GetLargestPossibleRegion());
   img->SetBufferedRegion( m_VectorImage->GetLargestPossibleRegion() );
   img->Allocate();
 
   int vecLength = m_VectorImage->GetVectorLength();
   InitializeByItk( img.GetPointer(), 1, vecLength );
 
   //for(int i=0; i<vecLength; i++)
   //{
   itk::ImageRegionIterator<ImgType> itw (img, img->GetLargestPossibleRegion() );
   itw = itw.Begin();
 
   itk::ImageRegionConstIterator<ImageType> itr (m_VectorImage, m_VectorImage->GetLargestPossibleRegion() );
   itr = itr.Begin();
 
   while(!itr.IsAtEnd())
   {
     itw.Set(itr.Get().GetElement(firstZeroIndex));
     ++itr;
     ++itw;
   }
 
   // init
   SetImportVolume(img->GetBufferPointer());//, 0, 0, CopyMemory);
   //SetVolume( img->GetBufferPointer(), i );
   //}
 
   m_DisplayIndex = firstZeroIndex;
   MITK_INFO << "Diffusion-Image successfully initialized.";
 
 }
 
 template<typename TPixelType>
 void mitk::DiffusionImage<TPixelType>
 ::SetDisplayIndexForRendering(int displayIndex)
 {
   int index = displayIndex;
   int vecLength = m_VectorImage->GetVectorLength();
   index = index > vecLength-1 ? vecLength-1 : index;
   if( m_DisplayIndex != index )
   {
     typedef itk::Image<TPixelType,3> ImgType;
     typename ImgType::Pointer img = ImgType::New();
     CastToItkImage<ImgType>(this, img);
 
     itk::ImageRegionIterator<ImgType> itw (img, img->GetLargestPossibleRegion() );
     itw = itw.Begin();
 
     itk::ImageRegionConstIterator<ImageType> itr (m_VectorImage, m_VectorImage->GetLargestPossibleRegion() );
     itr = itr.Begin();
 
     while(!itr.IsAtEnd())
     {
       itw.Set(itr.Get().GetElement(index));
       ++itr;
       ++itw;
     }
   }
 
   m_DisplayIndex = index;
 }
 
 
 //template<typename TPixelType>
 //bool mitk::DiffusionImage<TPixelType>::RequestedRegionIsOutsideOfTheBufferedRegion()
 //{
 //  return false;
 //}
 //
 //template<typename TPixelType>
 //void mitk::DiffusionImage<TPixelType>::SetRequestedRegion(itk::DataObject * /*data*/)
 //{
 //}
 //
 //template<typename TPixelType>
 //void mitk::DiffusionImage<TPixelType>::SetRequestedRegionToLargestPossibleRegion()
 //{
 //}
 //
 //template<typename TPixelType>
 //bool mitk::DiffusionImage<TPixelType>::VerifyRequestedRegion()
 //{
 //  return true;
 //}
 
 //template<typename TPixelType>
 //void mitk::DiffusionImage<TPixelType>::DuplicateIfSingleSlice()
 //{
 //  // new image
 //  typename ImageType::Pointer oldImage = m_Image;
 //  m_Image = ImageType::New();
 //  m_Image->SetSpacing( oldImage->GetSpacing() );   // Set the image spacing
 //  m_Image->SetOrigin( oldImage->GetOrigin() );     // Set the image origin
 //  m_Image->SetDirection( oldImage->GetDirection() );  // Set the image direction
 //  typename ImageType::RegionType region = oldImage->GetLargestPossibleRegion();
 //  if(region.GetSize(0) == 1)
 //    region.SetSize(0,3);
 //  if(region.GetSize(1) == 1)
 //    region.SetSize(1,3);
 //  if(region.GetSize(2) == 1)
 //    region.SetSize(2,3);
 //  m_Image->SetLargestPossibleRegion( region );
 //  m_Image->SetVectorLength( m_Directions->size() );
 //  m_Image->SetBufferedRegion( region );
 //  m_Image->Allocate();
 //
 //  // average image data that corresponds to identical directions
 //  itk::ImageRegionIterator< ImageType > newIt(m_Image, region);
 //  newIt.GoToBegin();
 //  itk::ImageRegionIterator< ImageType > oldIt(oldImage, oldImage->GetLargestPossibleRegion());
 //  oldIt.GoToBegin();
 //
 //  while(!newIt.IsAtEnd())
 //  {
 //    newIt.Set(oldIt.Get());
 //    ++newIt;
 //    ++oldIt;
 //    if(oldIt.IsAtEnd())
 //      oldIt.GoToBegin();
 //  }
 //
 //}
 
 template<typename TPixelType>
 bool mitk::DiffusionImage<TPixelType>::AreAlike(GradientDirectionType g1,
                                                 GradientDirectionType g2,
                                                 double precision)
 {
   GradientDirectionType diff = g1 - g2;
   return diff.two_norm() < precision;
 }
 
 template<typename TPixelType>
 void mitk::DiffusionImage<TPixelType>::CorrectDKFZBrokenGradientScheme(double precision)
 {
   GradientDirectionContainerType::Pointer directionSet = CalcAveragedDirectionSet(precision, m_Directions);
   if(directionSet->size() < 7)
   {
     MITK_INFO << "Too few directions, assuming and correcting DKFZ-bogus sequence details.";
 
     double v [7][3] =
     {{ 0,         0,         0        },
      {-0.707057,  0,         0.707057 },
      { 0.707057,  0,         0.707057 },
      { 0,         0.707057,  0.707057 },
      { 0,         0.707057, -0.707057 },
      {-0.707057,  0.707057,  0        },
      { 0.707057,  0.707057,  0        } };
 
     int i=0;
 
     for(GradientDirectionContainerType::Iterator it = m_OriginalDirections->Begin();
         it != m_OriginalDirections->End(); ++it)
     {
       it.Value().set(v[i++%7]);
     }
     ApplyMeasurementFrame();
   }
 }
 
 template<typename TPixelType>
 mitk::DiffusionImage<TPixelType>::GradientDirectionContainerType::Pointer
 mitk::DiffusionImage<TPixelType>::CalcAveragedDirectionSet(double precision, GradientDirectionContainerType::Pointer directions)
 {
   // save old and construct new direction container
   GradientDirectionContainerType::Pointer newDirections = GradientDirectionContainerType::New();
 
   // fill new direction container
   for(GradientDirectionContainerType::ConstIterator gdcitOld = directions->Begin();
       gdcitOld != directions->End(); ++gdcitOld)
   {
     // already exists?
     bool found = false;
     for(GradientDirectionContainerType::ConstIterator gdcitNew = newDirections->Begin();
         gdcitNew != newDirections->End(); ++gdcitNew)
     {
       if(AreAlike(gdcitNew.Value(), gdcitOld.Value(), precision))
       {
         found = true;
         break;
       }
     }
 
     // if not found, add it to new container
     if(!found)
     {
       newDirections->push_back(gdcitOld.Value());
     }
   }
 
   return newDirections;
 }
 
 template<typename TPixelType>
 void mitk::DiffusionImage<TPixelType>::AverageRedundantGradients(double precision)
 {
 
   GradientDirectionContainerType::Pointer newDirs =
       CalcAveragedDirectionSet(precision, m_Directions);
 
   GradientDirectionContainerType::Pointer newOriginalDirs =
       CalcAveragedDirectionSet(precision, m_OriginalDirections);
 
   // if sizes equal, we do not need to do anything in this function
   if(m_Directions->size() == newDirs->size() || m_OriginalDirections->size() == newOriginalDirs->size())
     return;
 
   GradientDirectionContainerType::Pointer oldDirections = m_Directions;
   GradientDirectionContainerType::Pointer oldOriginalDirections = m_OriginalDirections;
   m_Directions = newDirs;
   m_OriginalDirections = newOriginalDirs;
 
   // new image
   typename ImageType::Pointer oldImage = m_VectorImage;
   m_VectorImage = ImageType::New();
   m_VectorImage->SetSpacing( oldImage->GetSpacing() );   // Set the image spacing
   m_VectorImage->SetOrigin( oldImage->GetOrigin() );     // Set the image origin
   m_VectorImage->SetDirection( oldImage->GetDirection() );  // Set the image direction
   m_VectorImage->SetLargestPossibleRegion( oldImage->GetLargestPossibleRegion() );
   m_VectorImage->SetVectorLength( m_Directions->size() );
   m_VectorImage->SetBufferedRegion( oldImage->GetLargestPossibleRegion() );
   m_VectorImage->Allocate();
 
   // average image data that corresponds to identical directions
   itk::ImageRegionIterator< ImageType > newIt(m_VectorImage, m_VectorImage->GetLargestPossibleRegion());
   newIt.GoToBegin();
   itk::ImageRegionIterator< ImageType > oldIt(oldImage, oldImage->GetLargestPossibleRegion());
   oldIt.GoToBegin();
 
   // initial new value of voxel
   typename ImageType::PixelType newVec;
   newVec.SetSize(m_Directions->size());
   newVec.AllocateElements(m_Directions->size());
 
   std::vector<std::vector<int> > dirIndices;
   for(GradientDirectionContainerType::ConstIterator gdcitNew = m_Directions->Begin();
       gdcitNew != m_Directions->End(); ++gdcitNew)
   {
     dirIndices.push_back(std::vector<int>(0));
     for(GradientDirectionContainerType::ConstIterator gdcitOld = oldDirections->Begin();
         gdcitOld != oldDirections->End(); ++gdcitOld)
     {
       if(AreAlike(gdcitNew.Value(), gdcitOld.Value(), precision))
       {
         dirIndices[gdcitNew.Index()].push_back(gdcitOld.Index());
       }
     }
   }
 
   //int ind1 = -1;
   while(!newIt.IsAtEnd())
   {
 
     // progress
     //typename ImageType::IndexType ind = newIt.GetIndex();
     //ind1 = ind.m_Index[2];
 
     // init new vector with zeros
     newVec.Fill(0.0);
 
     // the old voxel value with duplicates
     typename ImageType::PixelType oldVec = oldIt.Get();
 
     for(unsigned int i=0; i<dirIndices.size(); i++)
     {
       // do the averaging
       int numavg = dirIndices[i].size();
       for(int j=0; j<numavg; j++)
       {
         newVec[i] += oldVec[dirIndices[i].at(j)];
       }
       if(numavg == 0)
       {
         MITK_ERROR << "mitkDiffusionImage: Error on averaging. Possibly due to corrupted data";
         return;
       }
       newVec[i] /= numavg;
     }
 
     newIt.Set(newVec);
 
     ++newIt;
     ++oldIt;
   }
 
   std::cout << std::endl;
 }
 
 template<typename TPixelType>
 void mitk::DiffusionImage<TPixelType>::ApplyMeasurementFrame()
 {
+  RemoveDirectionsContainerObserver();
+
   m_Directions = GradientDirectionContainerType::New();
   int c = 0;
   for(GradientDirectionContainerType::ConstIterator gdcit = m_OriginalDirections->Begin();
       gdcit != m_OriginalDirections->End(); ++gdcit)
   {
     vnl_vector<double> vec = gdcit.Value();
     vec = vec.pre_multiply(m_MeasurementFrame);
     m_Directions->InsertElement(c, vec);
     c++;
   }
+
+  UpdateBValueList();
+
+  AddDirectionsContainerObserver();
+
+
 }
 
 // returns number of gradients
 template<typename TPixelType>
 int mitk::DiffusionImage<TPixelType>::GetNumDirections()
 {
   int gradients = m_OriginalDirections->Size();
   for (int i=0; i<m_OriginalDirections->Size(); i++)
     if (GetB_Value(i)<=0)
     {
       gradients--;
     }
   return gradients;
 }
 
 // returns number of not diffusion weighted images
 template<typename TPixelType>
 int mitk::DiffusionImage<TPixelType>::GetNumB0()
 {
   int b0 = 0;
   for (int i=0; i<m_OriginalDirections->Size(); i++)
     if (GetB_Value(i)<=0)
     {
       b0++;
     }
   return b0;
 }
 
 // returns a list of indices belonging to the not diffusion weighted images
 template<typename TPixelType>
 typename mitk::DiffusionImage<TPixelType>::IndicesVector mitk::DiffusionImage<TPixelType>::GetB0Indices()
 {
   IndicesVector indices;
   for (int i=0; i<m_OriginalDirections->Size(); i++)
     if (GetB_Value(i)<=0)
     {
       indices.push_back(i);
     }
   return indices;
 }
 
 template<typename TPixelType>
 bool mitk::DiffusionImage<TPixelType>::IsMultiBval()
 {
   int gradients = m_OriginalDirections->Size();
 
   for (int i=0; i<gradients; i++)
     if (GetB_Value(i)>0 && std::fabs(m_B_Value-GetB_Value(i))>50)
       return true;
   return false;
 }
 
 template<typename TPixelType>
 void mitk::DiffusionImage<TPixelType>::UpdateBValueList()
 {
-
-  MITK_INFO << " TEST123| MODIFIED OOOWWEEEE";
-  if(m_B_ValueMap.size() != 0)
-  {
-    m_B_ValueMap.clear();
-  }
+  m_B_ValueMap.clear();
 
   GradientDirectionContainerType::ConstIterator gdcit;
   for( gdcit = this->m_Directions->Begin(); gdcit != this->m_Directions->End(); ++gdcit)
   {
     float currentBvalue = std::floor(GetB_Value(gdcit.Index()));
     double rounded = int((currentBvalue+7.5)/10)*10;
     m_B_ValueMap[rounded].push_back(gdcit.Index());
   }
 
+  /*
+  BValueMap::iterator it = m_B_ValueMap.begin();
+  for(;it != m_B_ValueMap.end(); it++)
+  {
+    MITK_INFO << it->first << " : " << it->second.size();
+  }
+  */
+
 }
 
 template<typename TPixelType>
 float mitk::DiffusionImage<TPixelType>::GetB_Value(int i)
 {
   if(i > m_Directions->Size()-1)
     return -1;
 
   if(m_Directions->ElementAt(i).one_norm() <= 0.0)
   {
     return 0;
   }
   else
   {
     double twonorm = m_Directions->ElementAt(i).two_norm();
     return m_B_Value*twonorm*twonorm ;
   }
 }
 
 template<typename TPixelType>
 void mitk::DiffusionImage<TPixelType>::SetOriginalDirections(const std::vector<itk::Vector<double,3> > directions)
 {
   m_OriginalDirections = GradientDirectionContainerType::New();
   for(unsigned int i=0; i<directions.size(); i++)
   {
     m_OriginalDirections->InsertElement( i, directions[i].Get_vnl_vector() );
   }
   this->ApplyMeasurementFrame();
 }
 
 template<typename TPixelType>
 void mitk::DiffusionImage<TPixelType>::SetDirections(const std::vector<itk::Vector<double,3> > directions)
 {
+
+  RemoveDirectionsContainerObserver();
+
   m_Directions = GradientDirectionContainerType::New();
   for(unsigned int i=0; i<directions.size(); i++)
   {
     m_Directions->InsertElement( i, directions[i].Get_vnl_vector() );
   }
+
+  UpdateBValueList();
+  AddDirectionsContainerObserver();
+}
+
+template<typename TPixelType>
+void mitk::DiffusionImage<TPixelType>::AddDirectionsContainerObserver()
+{
+  // Add Modified Observer to invoke an UpdateBValueList by modifieng the DirectionsContainer (m_Directions)
+  typedef DiffusionImage< TPixelType > Self;
+  typedef itk::SimpleMemberCommand< Self >  DCCommand ;
+  typename DCCommand::Pointer command = DCCommand::New();
+  command->SetCallbackFunction(this, &Self::UpdateBValueList);
+}
+
+template<typename TPixelType>
+void mitk::DiffusionImage<TPixelType>::RemoveDirectionsContainerObserver()
+{
+  if(m_Directions){
+    m_Directions->RemoveAllObservers();
+  }
 }
+