Hi. Sorry, I don’t understand what you mean. The ‘light source’ is the physical light that is casting the light. Perhaps if you explain your problem in detail someone might be able to help more. The only thing that I can think of is that you want a layer in front of the lit object not to be affected by the light – in which case make sure the layer is 3D, twirl open its Properties, go to Material Options and set Accepts Lights to off.