diff --git a/imageviewer-qt4.cpp b/imageviewer-qt4.cpp
index 976f4f5..6e6676e 100644
--- a/imageviewer-qt4.cpp
+++ b/imageviewer-qt4.cpp
@@ -402,12 +402,14 @@ void ImageViewer::partialLinearHistogrammAdaption() {
     }
   }
   
+  double* original_histogramm = original->getRelativeCumulativeIntensityHistogramm();
+  
   // Build up the brightness map to apply on the image
   // (basically inversing the histogramm map)
   int* brightness_map = (int*) malloc(256*sizeof(int));
   int j=0;
   for(int i=0; i<256; i++) {
-    double old_cumulative_brightness = reference_histogramm[i];
+    double old_cumulative_brightness = original_histogramm[i];
     while(old_cumulative_brightness > histogramm_map[j]) j++;
     if(j > 255) j = 255;
     brightness_map[i] = j;