Thanks for all the great comments. Here's my try at a glow in the dark render for Mike K4ICY. I'm not entirely happy with it, but can't seem to get it to look much better. Any suggestions? I don't know enough about vacuum tube anatomy so I just make a glowy coil (cathode heater?) for each one and punched some holes in the cylinder I had inside the tubes so the light could come out. hehe.