the point of the UV light is that it only light up the white layout
if you leave the numbers black it will not glow.. the UV light is placed in front of the white layout (not LEDs behind
) therefor you dont need the light to penetrate
sorry if my english is bad.. let me know if you dont understand. BTW if you bye a GOOD matt photopaper iy dont have any visible grinds
(the UV light I'm going to use is the same kind you will find in your "modded" computer
)