diff --git a/fcl/protodunevd/g4/protodunevd_g4_stage2.fcl b/fcl/protodunevd/g4/protodunevd_g4_stage2.fcl
index 313aeab2..3ed4bc53 100644
--- a/fcl/protodunevd/g4/protodunevd_g4_stage2.fcl
+++ b/fcl/protodunevd/g4/protodunevd_g4_stage2.fcl
@@ -17,7 +17,9 @@ services:
   NuRandomService:       @local::dune_prod_seedservice
 }
 
-
+# Test parameters for ScintPreScale in ProtoDUNE VD Cosmic Simulation
+services.OpDetResponseInterface.QuantumEfficiency: 0.2
+services.LArPropertiesService.ScintPreScale: 0.2
 
 source:
 {