diff --git a/doc/changelog.dox b/doc/changelog.dox
index 0c543693c..39eef6aa9 100644
--- a/doc/changelog.dox
+++ b/doc/changelog.dox
@@ -145,6 +145,9 @@ See also:
 -   For meshes with multiple sets of vertex attributes (such as texture
     coordinates), @ref MeshTools::compile() should be using only the first set
     but it wasn't.
+-   @ref Shaders::Phong was normalizing light direction in vertex shader,
+    causing the fragment-interpolated direction being incorrect with visible
+    artifacts on long polygons under low light angle
 
 @subsection changelog-latest-deprecated Deprecated APIs
 
diff --git a/src/Magnum/MeshTools/Test/CompileTestFiles/phong-flat.tga b/src/Magnum/MeshTools/Test/CompileTestFiles/phong-flat.tga
index 3b9e47aba..4947cdb13 100644
Binary files a/src/Magnum/MeshTools/Test/CompileTestFiles/phong-flat.tga and b/src/Magnum/MeshTools/Test/CompileTestFiles/phong-flat.tga differ
diff --git a/src/Magnum/MeshTools/Test/CompileTestFiles/phong-smooth.tga b/src/Magnum/MeshTools/Test/CompileTestFiles/phong-smooth.tga
index ddc81ed34..07f653f90 100644
Binary files a/src/Magnum/MeshTools/Test/CompileTestFiles/phong-smooth.tga and b/src/Magnum/MeshTools/Test/CompileTestFiles/phong-smooth.tga differ
diff --git a/src/Magnum/MeshTools/Test/CompileTestFiles/phong.tga b/src/Magnum/MeshTools/Test/CompileTestFiles/phong.tga
index 89dd5beec..c952c51a2 100644
Binary files a/src/Magnum/MeshTools/Test/CompileTestFiles/phong.tga and b/src/Magnum/MeshTools/Test/CompileTestFiles/phong.tga differ
diff --git a/src/Magnum/Shaders/Phong.vert b/src/Magnum/Shaders/Phong.vert
index 3a76a6766..c89ee394a 100644
--- a/src/Magnum/Shaders/Phong.vert
+++ b/src/Magnum/Shaders/Phong.vert
@@ -180,7 +180,7 @@ void main() {
 
     /* Direction to the light */
     for(int i = 0; i < LIGHT_COUNT; ++i)
-        lightDirections[i] = normalize(lightPositions[i] - transformedPosition);
+        lightDirections[i] = lightPositions[i] - transformedPosition;
 
     /* Direction to the camera */
     cameraDirection = -transformedPosition;
diff --git a/src/Magnum/Shaders/Test/PhongTestFiles/defaults.tga b/src/Magnum/Shaders/Test/PhongTestFiles/defaults.tga
index f9a499b35..83e4a1818 100644
Binary files a/src/Magnum/Shaders/Test/PhongTestFiles/defaults.tga and b/src/Magnum/Shaders/Test/PhongTestFiles/defaults.tga differ
diff --git a/src/Magnum/Shaders/Test/PhongTestFiles/textured-normal.tga b/src/Magnum/Shaders/Test/PhongTestFiles/textured-normal.tga
index 679a3b3ce..87b5d7ea6 100644
Binary files a/src/Magnum/Shaders/Test/PhongTestFiles/textured-normal.tga and b/src/Magnum/Shaders/Test/PhongTestFiles/textured-normal.tga differ