diff --git a/src/osg/CullStack.cpp b/src/osg/CullStack.cpp
index 0908968db..08c4791c1 100644
--- a/src/osg/CullStack.cpp
+++ b/src/osg/CullStack.cpp
@@ -74,8 +74,8 @@ void CullStack::pushCullingSet()
                            M(2,0)*P00 + M(2,2)*P20_00);
                            
         // scaling for vertical pixels
-        float P10 = P(1,1)*W.width()*0.5f;
-        float P20_10 = P(2,1)*W.width()*0.5f + P(2,3)*W.width()*0.5f;
+        float P10 = P(1,1)*W.height()*0.5f;
+        float P20_10 = P(2,1)*W.height()*0.5f + P(2,3)*W.height()*0.5f;
         osg::Vec3 scale_10(M(0,1)*P10 + M(0,2)*P20_10,
                            M(1,1)*P10 + M(1,2)*P20_10,
                            M(2,1)*P10 + M(2,2)*P20_10);