diff --git a/reg23Topograms/itkDTRrecon/autoreg/itkMutualInformationTwoImageToOneImageMetric.h b/reg23Topograms/itkDTRrecon/autoreg/itkMutualInformationTwoImageToOneImageMetric.h
index 678d7c0..bed071c 100644
--- a/reg23Topograms/itkDTRrecon/autoreg/itkMutualInformationTwoImageToOneImageMetric.h
+++ b/reg23Topograms/itkDTRrecon/autoreg/itkMutualInformationTwoImageToOneImageMetric.h
@@ -95,6 +95,7 @@ public:
    * typically results in narrower valleys in the cost fucntion.
    * Default value is false. */
     itkSetMacro(SubtractMean, bool);
+    itkSetMacro(NumberOfHistogramBins, int);
     itkGetConstReferenceMacro(SubtractMean, bool);
     itkBooleanMacro(SubtractMean);
 
@@ -106,6 +107,7 @@ protected:
 
 private:
     bool m_SubtractMean;
+    int m_NumberOfHistogramBins;
 };
 
 } // end namespace itk
diff --git a/reg23Topograms/itkDTRrecon/autoreg/itkMutualInformationTwoImageToOneImageMetric.hxx b/reg23Topograms/itkDTRrecon/autoreg/itkMutualInformationTwoImageToOneImageMetric.hxx
index b7c03a7..070f6ba 100644
--- a/reg23Topograms/itkDTRrecon/autoreg/itkMutualInformationTwoImageToOneImageMetric.hxx
+++ b/reg23Topograms/itkDTRrecon/autoreg/itkMutualInformationTwoImageToOneImageMetric.hxx
@@ -36,6 +36,7 @@ MutualInformationTwoImageToOneImageMetric<TFixedImage,
     TMovingImage>::MutualInformationTwoImageToOneImageMetric()
 {
     m_SubtractMean = false;
+    m_NumberOfHistogramBins = 50;
 }
 
 template <typename TFixedImage, typename TMovingImage>
@@ -147,7 +148,8 @@ MutualInformationTwoImageToOneImageMetric<TFixedImage, TMovingImage>::GetValue()
     //auto numberOfSamples = static_cast<unsigned int>(numberOfPixels * 0.50); //100%
     // since we have a ROI, then we should not set allPixels to TRUE.
     //metric1->UseAllPixelsOn();
-    metric1->SetNumberOfHistogramBins(50);
+    std::cout << "m_NumberOfHistogramBins " << m_NumberOfHistogramBins << std::endl;
+    metric1->SetNumberOfHistogramBins(m_NumberOfHistogramBins);
 
 //    InternalImageType::IndexType pIndex;
 //    pIndex[0]=200;
@@ -183,7 +185,7 @@ MutualInformationTwoImageToOneImageMetric<TFixedImage, TMovingImage>::GetValue()
     //numberOfSamples = static_cast<unsigned int>(numberOfPixels * 0.50); //100%
     //metric2->SetNumberOfSpatialSamples(numberOfSamples);
     //metric2->UseAllPixelsOn();
-    metric2->SetNumberOfHistogramBins(50);
+    metric2->SetNumberOfHistogramBins(m_NumberOfHistogramBins);
     metric2->SetFixedImage(fixedImage2);
     metric2->SetMovingImage(this->m_Filter2->GetOutput());
     metric2->Initialize();
diff --git a/reg23Topograms/itkDTRrecon/itkImageProcessor.cpp b/reg23Topograms/itkDTRrecon/itkImageProcessor.cpp
index 3a4b16a..8251e34 100644
--- a/reg23Topograms/itkDTRrecon/itkImageProcessor.cpp
+++ b/reg23Topograms/itkDTRrecon/itkImageProcessor.cpp
@@ -1236,8 +1236,9 @@ void itkImageProcessor::SetAmoebaOptimParameters(
 
 }
 
-void itkImageProcessor::SetMIMetricParameters(double dMaxT){
+void itkImageProcessor::SetMIMetricParameters(double dMaxT,int iNhb){
     m_MIMetricMetaInfo->SetMaxTranslation(dMaxT);
+    m_MIMetricMetaInfo->SetNumberOfHistogramBins(iNhb);
 }
 
 void itkImageProcessor::SetNCCMetricParameters(double dMaxT,bool bSm){
diff --git a/reg23Topograms/itkDTRrecon/itkImageProcessor.h b/reg23Topograms/itkDTRrecon/itkImageProcessor.h
index 7263c9e..ff1e9af 100644
--- a/reg23Topograms/itkDTRrecon/itkImageProcessor.h
+++ b/reg23Topograms/itkDTRrecon/itkImageProcessor.h
@@ -111,7 +111,7 @@ public:
     void SetAmoebaOptimParameters(double,double,double,int);
 
     /** Set MI */
-    void SetMIMetricParameters(double);
+    void SetMIMetricParameters(double,int);
 
     /** Set NCC */
     void SetNCCMetricParameters(double,bool);
diff --git a/reg23Topograms/itkDTRrecon/itkReg23.cpp b/reg23Topograms/itkDTRrecon/itkReg23.cpp
index 9dbcbe1..4ba0e29 100644
--- a/reg23Topograms/itkDTRrecon/itkReg23.cpp
+++ b/reg23Topograms/itkDTRrecon/itkReg23.cpp
@@ -13,6 +13,7 @@ itkReg23::itkReg23()
     NCCmetric = MetricType::New();
     MImetric = MIMetricType::New();
 
+
     // Optimizers
     PowellOptimizer = PowellOptimizerType::New();
     AmoebaOptimizer = AmoebaOptimizerType::New();
@@ -205,6 +206,7 @@ void itkReg23::InitializeRegistration()
         std::cout<< "Using MI Metric" <<std::endl;
 
         registration->SetMetric(MImetric);
+        MImetric->SetNumberOfHistogramBins(m_MIMeta->GetNumberOfHistogramBins());
         MImetric->ComputeGradientOff();
         MImetric->SetMaxTranslation(m_MIMeta->GetMaxTranslation());
 
diff --git a/reg23Topograms/itkDTRrecon/itkReg23MetaInformation.cpp b/reg23Topograms/itkDTRrecon/itkReg23MetaInformation.cpp
index 2cabe7f..32d94a7 100644
--- a/reg23Topograms/itkDTRrecon/itkReg23MetaInformation.cpp
+++ b/reg23Topograms/itkDTRrecon/itkReg23MetaInformation.cpp
@@ -59,6 +59,7 @@ MIMetricMetaInformation::
 MIMetricMetaInformation(){
 
     this->m_MaxTranslation = 100.0;
+    this->m_NumberOfHistogramBins = 50;
 
 }
 
diff --git a/reg23Topograms/itkDTRrecon/itkReg23MetaInformation.h b/reg23Topograms/itkDTRrecon/itkReg23MetaInformation.h
index 67c2f37..45d1c5c 100644
--- a/reg23Topograms/itkDTRrecon/itkReg23MetaInformation.h
+++ b/reg23Topograms/itkDTRrecon/itkReg23MetaInformation.h
@@ -150,11 +150,15 @@ public:
     itkSetMacro(MaxTranslation,double);
     itkGetMacro(MaxTranslation,double);
 
+    itkSetMacro(NumberOfHistogramBins,int);
+    itkGetMacro(NumberOfHistogramBins,int);
 
 protected:
 
     double m_MaxTranslation;
 
+    int m_NumberOfHistogramBins;
+
 
     /** Default Constructor **/
     MIMetricMetaInformation  ();