diff --git a/indra/newview/app_settings/shaders/class1/deferred/materialF.glsl b/indra/newview/app_settings/shaders/class1/deferred/materialF.glsl
index bf824b3afeb6e07868e6b12d50cf63a93ff92c82..f9dd0b2dd96b662cbae6678dead0a3a35ca9c1e7 100644
--- a/indra/newview/app_settings/shaders/class1/deferred/materialF.glsl
+++ b/indra/newview/app_settings/shaders/class1/deferred/materialF.glsl
@@ -357,7 +357,7 @@ void main()
             float scol = fres*texture2D(lightFunc, vec2(nh, spec.a)).r*gt / (nh*da);
             vec3 sp = sun_contrib*scol / 6.0f;
             sp = clamp(sp, vec3(0), vec3(1));
-            bloom = dot(sp, sp) / 4.0;
+            bloom += dot(sp, sp) / 4.0;
             color += sp * spec.rgb;
         }
 #else // PRODUCTION