diff --git a/binding/osfm-screen-binding.cpp b/binding/osfm-screen-binding.cpp
index fa61833d7..86e346cd7 100644
--- a/binding/osfm-screen-binding.cpp
+++ b/binding/osfm-screen-binding.cpp
@@ -53,7 +53,7 @@ struct PingPong {
     }
     
     void clearBuffers() {
-        glState.clearColor.pushSet(Vec4(0, 0, 0, 1));
+        glState.clearColor.pushSet(Vec4(0, 0, 0, 0));
         
         for (int i = 0; i < 2; ++i) {
             FBO::bind(rt[i].fbo);
diff --git a/src/display/gl/glstate.cpp b/src/display/gl/glstate.cpp
index cfafe344f..ac279c3e2 100644
--- a/src/display/gl/glstate.cpp
+++ b/src/display/gl/glstate.cpp
@@ -85,7 +85,7 @@ void GLBlendMode::apply(const BlendType &value) {
 
   case BlendAddition:
     gl.BlendEquation(GL_FUNC_ADD);
-    gl.BlendFuncSeparate(GL_SRC_ALPHA, GL_ONE, GL_ONE, GL_ONE);
+    gl.BlendFuncSeparate(GL_ONE, GL_ONE, GL_ZERO, GL_ONE);
     break;
 
   case BlendSubstraction: