So I am trying to create the effect of low light vision with my players by having an extra light source that I will be moving around with them as they walk around that has twice the radius of light emitted as they do. They are walking around holding a torch so they are emitting 20 feet of normal light and another 20 feet of dim light. The extra light source will be on top of them and have a radius of 40 and 80. The problem I am running into is trying to figure out how to make this light source only visible to the players that have low light vision and not visible to the players that have normal vision. I am using Updated Dynamic Lighting with Explorer mode.