..and a 24v bulb should near double in lifespan at 12v, 50% longer at 18v., etc..
You need to vent the medicine bottle too. A hole on top & bottom. Down low you can block off white light easy with a flat...tab? etc. away from but in front of the hole. On top, another bottle's trimmed bottom only; like a smokestack/vent cap; catching and yellowing the "white light beam" from the vent hole(s) (vs blocking and in turn reflecting the light some, is going to change the look too. I'd play with both to see.
They also make slip on color gels for most bulbs. red, amber, yellow, blue, green. Silicon doesn't melt . A covered, hot bulb's expected cooling rate off the glass can be comprimised though, shortening life and cutting fingers on removal if the bulb glass gets shocked along a hot/cold line on the glass at the rubbers edge. Great on cool burning bulbs though. Some are very translucent, others more opaque.
