diff --git a/tools/quake3/q3map2/light_ydnar.c b/tools/quake3/q3map2/light_ydnar.c
index e11f3400..801ef5ac 100644
--- a/tools/quake3/q3map2/light_ydnar.c
+++ b/tools/quake3/q3map2/light_ydnar.c
@@ -2101,11 +2101,14 @@ void IlluminateRawLightmap( int rawLightmapNum )
 					/* add to light direction map (fixme: use luxel normal as starting point for deluxel?) */
 					if( deluxemap )
 					{
-						/* color to grayscale (photoshop rgb weighting) */
-						brightness = trace.color[ 0 ] * 0.3f + trace.color[ 1 ] * 0.59f + trace.color[ 2 ] * 0.11f;
-						brightness *= (1.0 / 255.0);
-						VectorScale( trace.direction, brightness, trace.direction );
-						VectorAdd( deluxel, trace.direction, deluxel );
+						if(DotProduct(normal, trace.direction) > 0) // do not take light from the back side
+						{
+							/* color to grayscale (photoshop rgb weighting) */
+							brightness = trace.color[ 0 ] * 0.3f + trace.color[ 1 ] * 0.59f + trace.color[ 2 ] * 0.11f;
+							brightness *= (1.0 / 255.0);
+							VectorScale( trace.direction, brightness, trace.direction );
+							VectorAdd( deluxel, trace.direction, deluxel );
+						}
 					}
 				}
 			}