diff --git a/Modules/PhotoacousticsLib/test/mitkSpectralUnmixingTest.cpp b/Modules/PhotoacousticsLib/test/mitkSpectralUnmixingTest.cpp
index 8d6e9516b8..d5db505a12 100644
--- a/Modules/PhotoacousticsLib/test/mitkSpectralUnmixingTest.cpp
+++ b/Modules/PhotoacousticsLib/test/mitkSpectralUnmixingTest.cpp
@@ -1,141 +1,139 @@
 ///*===================================================================
 
 //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 <mitkTestFixture.h>
 #include <mitkTestingMacros.h>
 
 #include <mitkPASpectralUnmixingFilterBase.h>
 #include <mitkPALinearSpectralUnmixingFilter.h>
 #include <mitkImageReadAccessor.h>
 
 class mitkSpectralUnmixingTestSuite : public mitk::TestFixture
 {
   CPPUNIT_TEST_SUITE(mitkSpectralUnmixingTestSuite);
   MITK_TEST(testSUAlgorithm);
   CPPUNIT_TEST_SUITE_END();
 
 private:
   mitk::pa::SpectralUnmixingFilterBase::Pointer m_SpectralUnmixingFilter;
   mitk::Image::Pointer inputImage;
   std::vector<float> m_inputWavelengths;
   std::vector<float> m_CorrectResult;
 
 public:
 
   void setUp() override
   {
     MITK_INFO << "setUp ... ";
     //Set empty input image:
     inputImage = mitk::Image::New();
     mitk::PixelType pixelType = mitk::MakeScalarPixelType<float>();
     const int NUMBER_OF_SPATIAL_DIMENSIONS = 3;
     auto* dimensions = new unsigned int[NUMBER_OF_SPATIAL_DIMENSIONS];
 
     dimensions[0] = 1;
     dimensions[1] = 1;
     dimensions[2] = 3;
 
     //Initialie empty input image:
     inputImage->Initialize(pixelType, NUMBER_OF_SPATIAL_DIMENSIONS, dimensions);
 
     //Set wavelengths for unmixing:
     m_inputWavelengths.push_back(750);
     m_inputWavelengths.push_back(800);
     m_inputWavelengths.push_back(850);
 
     //Set fraction of Hb and HbO2 to unmix:
     float fracHb = 0.3;
     float fracHbO2 = 0.67;
 
     //Fractions are also correct unmixing result:
-    m_CorrectResult.push_back(fracHb);
     m_CorrectResult.push_back(fracHbO2);
+    m_CorrectResult.push_back(fracHb);
 
     //Calculate values of wavelengths (750,800,850 nm) and multiply with fractions to get pixel values:
     float px1 = fracHb * 7.52 + fracHbO2 * 2.77;
     float px2 = fracHb * 4.08 + fracHbO2 * 4.37;
     float px3 = fracHb * 3.7 + fracHbO2 * 5.67;
     std::vector<float> m_Value{px1,px2,px3};
 
     float* data = new float[3];
     data[0] = m_Value[0];
     data[1] = m_Value[1];
     data[2] = m_Value[2];
 
     MITK_INFO << "data0 " << data[0];
     MITK_INFO << "data1 " << data[1];
     MITK_INFO << "data2 " << data[2];
 
     inputImage->SetImportVolume(data, mitk::Image::ImportMemoryManagementType::CopyMemory);
     delete[] data;
 
-    //Set input into filter
+    MITK_INFO << "[DONE]";
+  }
+
+  void testSUAlgorithm()
+  {
+    MITK_INFO << "START FILTER TEST ... ";
+    // Set input image
     auto m_SpectralUnmixingFilter = mitk::pa::LinearSpectralUnmixingFilter::New();
     m_SpectralUnmixingFilter->SetInput(inputImage);
 
     // Set Algortihm to filter
     m_SpectralUnmixingFilter->SetAlgorithm(mitk::pa::LinearSpectralUnmixingFilter::AlgortihmType::householderQr);
 
     //Set wavelengths to filter
     for (unsigned int imageIndex = 0; imageIndex < m_inputWavelengths.size(); imageIndex++)
     {
       unsigned int wavelength = m_inputWavelengths[imageIndex];
       m_SpectralUnmixingFilter->AddWavelength(wavelength);
     }
 
     //Set Chromophores to filter
     m_SpectralUnmixingFilter->AddChromophore(
       mitk::pa::SpectralUnmixingFilterBase::ChromophoreType::OXYGENATED_HEMOGLOBIN);
 
     m_SpectralUnmixingFilter->AddChromophore(
       mitk::pa::SpectralUnmixingFilterBase::ChromophoreType::DEOXYGENATED_HEMOGLOBIN);
 
-    MITK_INFO << "[DONE]";
-  }
-
-  void testSUAlgorithm()
-  {
-    MITK_INFO << "START FILTER TEST ... ";
-    auto m_LinearSpectralUnmixing = mitk::pa::LinearSpectralUnmixingFilter::New();
-    auto m_SpectralUnmixingFilter = mitk::pa::LinearSpectralUnmixingFilter::New();
-    m_LinearSpectralUnmixing->SetInput(inputImage);
-
-    //compare filter result (output) with theoretical result
+    m_SpectralUnmixingFilter->Update();
     float threshold = 1e-5;
+
     for (int i = 0; i < 2; ++i)
     {
       mitk::Image::Pointer output = m_SpectralUnmixingFilter->GetOutput(i);
-
       mitk::ImageReadAccessor readAccess(output);
-
       const float* inputDataArray = ((const float*)readAccess.GetData());
-
       auto pixel = inputDataArray[0];
-      CPPUNIT_ASSERT((pixel - m_CorrectResult[i])<threshold);
+
+      MITK_INFO << "CorrectResult: " << m_CorrectResult[i];
+      MITK_INFO << "FilterResult: " << pixel;
+
+      CPPUNIT_ASSERT(std::abs(pixel - m_CorrectResult[i])<threshold);
     }
     MITK_INFO << "FILTER TEST SUCCESFULL :)";
   }
 
   void tearDown() override
   {
     m_SpectralUnmixingFilter = nullptr;
     inputImage = nullptr;
     m_inputWavelengths.clear();
     m_CorrectResult.clear();
     MITK_INFO << "tearDown ... [DONE]";
   }
 };
 
 MITK_TEST_SUITE_REGISTRATION(mitkSpectralUnmixing)