diff --git a/hough_machine.cpp b/hough_machine.cpp
index d12a86e..7ffaf64 100644
--- a/hough_machine.cpp
+++ b/hough_machine.cpp
@@ -70,7 +70,7 @@ class HoughMachine {
 	  QColor pixel = QColor::fromRgb(this->original->getPixel(u, v, LazyImage::DEFAULT));
 	  int h, s, l;
 	  pixel.getHsl(&h, &s, &l);
-	  if(l > 0) {
+	  if(l < 15) {
 	    this->doPixel(u, v);
 	  }
 	}