I had a question on Etsy about how bright the Fallout 4 style “Nuka Cola” keyrings glow if you put Tritium capsules in, compared to just the regular glow-in-the-dark material. Note that I don’t sell the capsules myself, you’d need to source your own but they’re pretty readily available on eBay.
It’s difficult to give a totally objective set of images, but hopefully these comparisons are useful. In the first image, you can see the three capsules beside the keyrings. In normal light they just appear white.
Switch the lights off, and you can see the phosphor glow. They’re available in various colours, these are ‘Ice Blue’.
So, here I’ve put all three capsules into the key fob with the blue tag. The large LED light is what I’ll use to charge up the glow-in-the-dark plastic.
Charging them up. Note this is only charging the plastic, the capsules don’t need charging and will glow continuously for around 10 years.
And lights off!
Although they’re both glowing pretty brightly as soon as you remove the lights, you can still see the Tritium capsules glowing through the plastic (above).
10 seconds later, the green glow falls off pretty quickly (above)
30 seconds in and the green glow is starting to fade, while the capsules continue to glow…
After about a minute, the plastic glow is hard to see now unless the room is totally dark, but of course no difference to the Tritium one.
Even when the plastic has all-but stopped glowing, the Tritium keyring looks the same. As it will for about 10 years… Sort of. The Tritium in the capsules has a half life of 12 years, which means that every 12 years, half of the Tritium will have converted into helium & will be half as effective at making the phosphors glow. But compared to the glow-in-the-dark plastic, it’s basically continous light.