diff --git a/Algorithms/douglas_peucker.cpp b/Algorithms/douglas_peucker.cpp
index fdf7b2ba6..789983e68 100644
--- a/Algorithms/douglas_peucker.cpp
+++ b/Algorithms/douglas_peucker.cpp
@@ -100,7 +100,7 @@ void DouglasPeucker::Run(RandomAccessIt begin, RandomAccessIt end, const unsigne
     std::prev(end)->necessary = true;
 
     {
-        BOOST_ASSERT_MSG(zoom_level < 19, "unsupported zoom level");
+        BOOST_ASSERT_MSG(zoom_level < DOUGLAS_PEUCKER_THRESHOLDS.size(), "unsupported zoom level");
         RandomAccessIt left_border = begin;
         RandomAccessIt right_border = std::next(begin);
         // Sweep over array and identify those ranges that need to be checked
diff --git a/UnitTests/Algorithms/DouglasPeuckerTest.cpp b/UnitTests/Algorithms/DouglasPeuckerTest.cpp
index 2c0c54e98..ea979e9bb 100644
--- a/UnitTests/Algorithms/DouglasPeuckerTest.cpp
+++ b/UnitTests/Algorithms/DouglasPeuckerTest.cpp
@@ -32,7 +32,7 @@ BOOST_AUTO_TEST_CASE(all_necessary_test)
         getTestInfo(5, 15, true)
     };
     DouglasPeucker dp;
-    for (unsigned z = 0; z < 20; z++)
+    for (unsigned z = 0; z < DOUGLAS_PEUCKER_THRESHOLDS.size(); z++)
     {
         dp.Run(info, z);
         for (const auto& i : info)
@@ -45,7 +45,7 @@ BOOST_AUTO_TEST_CASE(all_necessary_test)
 BOOST_AUTO_TEST_CASE(remove_second_node_test)
 {
     DouglasPeucker dp;
-    for (unsigned z = 0; z < 19; z++)
+    for (unsigned z = 0; z < DOUGLAS_PEUCKER_THRESHOLDS.size(); z++)
     {
         /*
          *   x--x
@@ -68,9 +68,8 @@ BOOST_AUTO_TEST_CASE(remove_second_node_test)
             getTestInfo(5  * COORDINATE_PRECISION + DOUGLAS_PEUCKER_THRESHOLDS[z],
                         15 * COORDINATE_PRECISION, true),
         };
-        std::cout << "Threshold: " << DOUGLAS_PEUCKER_THRESHOLDS[z] << std::endl;
+        BOOST_TEST_MESSAGE("Threshold (" << z << "): " << DOUGLAS_PEUCKER_THRESHOLDS[z]);
         dp.Run(info, z);
-        std::cout << "z: " << z << std::endl;
         BOOST_CHECK_EQUAL(info[0].necessary, true);
         BOOST_CHECK_EQUAL(info[1].necessary, false);
         BOOST_CHECK_EQUAL(info[2].necessary, true);