diff --git a/wadsrc/static/shaders/glsl/main.fp b/wadsrc/static/shaders/glsl/main.fp
index 0fdd3abdd..013a1881e 100644
--- a/wadsrc/static/shaders/glsl/main.fp
+++ b/wadsrc/static/shaders/glsl/main.fp
@@ -25,7 +25,7 @@ vec3 ProcessMaterial(vec3 material, vec3 color);
 
 float grayscale(vec4 color)
 {
-	return dot(color.rgb, vec3(0.4, 0.56, 0.14));
+	return dot(color.rgb, vec3(0.3, 0.56, 0.14));
 }
 
 //===========================================================================