Joel another way to make the image dimmer is to add paper sheets over the diffuser, this is what one guy did when he had a too bright diffuser image, as I said in our emails, I have never encountered this before, interesting to say the least
The light you see coming through the diffuser in my light boxes is not direct led illumination, as their output is aimed at the white rear interior and you see this. it is like looking at a projected screen through the diffuser.