diff --git a/Modules/Core/include/mitkDataNode.h b/Modules/Core/include/mitkDataNode.h
index 5a445f5..6621bf0 100644
--- a/Modules/Core/include/mitkDataNode.h
+++ b/Modules/Core/include/mitkDataNode.h
@@ -70,6 +70,7 @@ public:
   typedef mitk::Geometry3D::Pointer Geometry3DPointer;
   typedef std::vector< itk::SmartPointer< Mapper > > MapperVector;
   typedef std::map<std::string, mitk::PropertyList::Pointer> MapOfPropertyLists;
+  typedef std::vector<MapOfPropertyLists::key_type> PropertyListKeyNames;
   typedef std::set<std::string> GroupTagList;
 
   /**
@@ -136,6 +137,14 @@ public:
   virtual void CopyInformation(const itk::DataObject *data) override;
 
   /**
+   * \brief return the keys of all PropertyLists.
+   *
+   * All possible values for the "renderer" parameters of
+   * the diverse GetProperty/List() methods.
+   */
+  PropertyListKeyNames GetPropertyListNames() const;
+
+  /**
    * \brief Set the property (instance of BaseProperty) with key \a propertyKey in the PropertyList
    * of the \a renderer (if NULL, use BaseRenderer-independent PropertyList). This is set-by-value.
    *
diff --git a/Modules/Core/include/mitkGeometryData.h b/Modules/Core/include/mitkGeometryData.h
index 72022a8..edc68a5 100644
--- a/Modules/Core/include/mitkGeometryData.h
+++ b/Modules/Core/include/mitkGeometryData.h
@@ -54,5 +54,16 @@ protected:
   virtual ~GeometryData();
 };
 
+/**
+* @brief Equal Compare two GeometryData objects for equality, returns true if found equal.
+* @ingroup MITKTestingAPI
+* @param rightHandSide GeometryData to compare.
+* @param leftHandSide GeometryData to compare.
+* @param eps Epsilon to use for floating point comparison. Most of the time mitk::eps will be sufficient.
+* @param verbose Flag indicating if the method should give a detailed console output.
+* @return True if every comparison is true, false in any other case.
+*/
+MITKCORE_EXPORT bool Equal( mitk::GeometryData& leftHandSide, mitk::GeometryData& rightHandSide, mitk::ScalarType eps, bool verbose);
+
 } // namespace mitk
 #endif /* MITKGEOMETRYDATA_H_HEADER_INCLUDED_C19C01E2 */
diff --git a/Modules/Core/src/DataManagement/mitkDataNode.cpp b/Modules/Core/src/DataManagement/mitkDataNode.cpp
index cd0912a..a090822 100644
--- a/Modules/Core/src/DataManagement/mitkDataNode.cpp
+++ b/Modules/Core/src/DataManagement/mitkDataNode.cpp
@@ -185,6 +185,17 @@ void mitk::DataNode::SetRequestedRegion( const itk::DataObject * /*data*/)
 {
 }
 
+mitk::DataNode::PropertyListKeyNames mitk::DataNode::GetPropertyListNames() const
+{
+  PropertyListKeyNames result;
+
+  for (auto entries : m_MapOfPropertyLists)
+    result.push_back( entries.first );
+
+  return result;
+}
+
+
 void mitk::DataNode::CopyInformation(const itk::DataObject * /*data*/)
 {
 }
diff --git a/Modules/Core/src/DataManagement/mitkGeometryData.cpp b/Modules/Core/src/DataManagement/mitkGeometryData.cpp
index 0fb9352..1c893cc 100644
--- a/Modules/Core/src/DataManagement/mitkGeometryData.cpp
+++ b/Modules/Core/src/DataManagement/mitkGeometryData.cpp
@@ -17,6 +17,7 @@ See LICENSE.txt or http://www.mitk.org for details.
 
 #include "mitkGeometryData.h"
 #include "mitkBaseProcess.h"
+#include "mitkTimeGeometry.h"
 
 mitk::GeometryData::GeometryData()
 {
@@ -60,5 +61,29 @@ void mitk::GeometryData::CopyInformation(const itk::DataObject *)
 {
 }
 
-
-
+bool mitk::Equal( mitk::GeometryData& leftHandSide, mitk::GeometryData& rightHandSide, mitk::ScalarType eps, bool verbose)
+{
+  unsigned int timeStepsLeft = leftHandSide.GetTimeGeometry()->CountTimeSteps();
+  unsigned int timeStepsRight = rightHandSide.GetTimeGeometry()->CountTimeSteps();
+
+  if (timeStepsLeft != timeStepsRight)
+  {
+    if (verbose)
+    {
+      MITK_INFO << "[( GeometryData::GetTimeGeometry )] number of time steps are not equal.";
+      MITK_INFO << "rightHandSide is " << timeStepsRight << " : leftHandSide is " << timeStepsLeft;
+    }
+    return false;
+  }
+
+  bool allEqual = true;
+
+  for (unsigned int t = 0; t < timeStepsLeft; ++t)
+  {
+    BaseGeometry* geomLeft = leftHandSide.GetGeometry(t);
+    BaseGeometry* geomRight = rightHandSide.GetGeometry(t);
+    allEqual &= mitk::Equal(*geomLeft, *geomRight, eps, verbose);
+  }
+
+  return allEqual; // valid with initial true for timestep count == 0
+}
diff --git a/Modules/Core/src/DataManagement/mitkLevelWindow.cpp b/Modules/Core/src/DataManagement/mitkLevelWindow.cpp
index 4085970..9f2fda8 100644
--- a/Modules/Core/src/DataManagement/mitkLevelWindow.cpp
+++ b/Modules/Core/src/DataManagement/mitkLevelWindow.cpp
@@ -425,15 +425,14 @@ bool mitk::LevelWindow::IsFixed() const
 
 bool mitk::LevelWindow::operator==(const mitk::LevelWindow& levWin) const
 {
-  if ( m_RangeMin == levWin.GetRangeMin() &&
-    m_RangeMax == levWin.GetRangeMax() &&
-    m_LowerWindowBound == levWin.GetLowerWindowBound() && m_UpperWindowBound == levWin.GetUpperWindowBound() &&
-    m_DefaultLowerBound == levWin.GetDefaultLowerBound() && m_DefaultUpperBound == levWin.GetDefaultUpperBound() && m_Fixed == levWin.IsFixed() ) {
-      return true;
-  }
-  else {
-    return false;
-  }
+  return ( fabs( m_RangeMin - levWin.GetRangeMin() ) < mitk::sqrteps &&
+       fabs(m_RangeMax - levWin.GetRangeMax()) < mitk::sqrteps &&
+       fabs(m_LowerWindowBound - levWin.GetLowerWindowBound()) < mitk::sqrteps &&
+       fabs(m_UpperWindowBound - levWin.GetUpperWindowBound()) < mitk::sqrteps &&
+       fabs(m_DefaultLowerBound - levWin.GetDefaultLowerBound()) < mitk::sqrteps &&
+       fabs(m_DefaultUpperBound - levWin.GetDefaultUpperBound()) < mitk::sqrteps &&
+       m_Fixed == levWin.IsFixed()
+       );
 }
 
 bool mitk::LevelWindow::operator!=(const mitk::LevelWindow& levWin) const