How to Choose the Right Nighttime Watch Illumination

A generation or so ago, a watch didn’t necessarily have glow-in-the-dark hands and hour markers. Sure, there was radium, but we all know how dangerous that can be if accidently ingested. It’s fortunate that watch manufacturers since the 1960s stopped using radium. So what has taken its place in the intervening years? There are many choices. Read on to find out the pros and cons of each choice.

Luminous Paint

There are many kinds of luminous paint compound used on watches today – some crummy and some remarkably good. The standard by which all others are judged is Super-LumiNova – a strontium aluminate pigment from the LumiNova company of Switzerland. Some manufacturers use similar compounds that provide illumination as good, for instance Seiko’s proprietary Lumi Brite comes to mind. These “lume” compounds, when held up to a bright light for around 30 seconds, should glow at least 8-9 hours in a dark room. One of the keys to a long-lasting glow is how wide the hands are, and consequently, how much paint surface there is.

Pros

All-night performance from the best paint

Not radioactive

Lasts for a long time – it takes a long time for it to degraded and lose its glowing properties

Cons

Needs to be “charged” by bright light

Cheaper paint compounds will disappoint by glowing for a very short amount of time

Hard to read in the half-light of morning as the glow wears off

Electric Lighting

Often featured on cheaper watches, such as digital ones or inexpensive quartz analog models, this form of illumination can take the form of a direct light or an electric backlight “glow” like Timex’s Indiglo. It’s a pretty straight-forward concept that everyone is familiar with.

Pros

Good illumination whenever it is needed

Inexpensive

Not radioactive

Cons

Runs down the battery faster

Only on quartz watches – more collectible hand-wound or automatics won’t have this feature

In most cases, you must push a button to see – it doesn’t glow in the dark without activation

Tritium

Even though radium has dropped out of favor, self-glowing, radioactive illumination for watches continues on to this day. As currently used, tritium is encased in glass vials that are attached to a watch’s hands and hour markers. Once the province of military-issue watches, tritium illumination is offered on several sub-$100 military-style models. Tritium is considered safe while encased inside the watch. It is not considered safe for watchmakers, though. You’ll typically see the tell-tale radioactive sign on military issue watches with tritium to give a heads-up to anyone working on such a watch.

Pros

Always illuminated and never needs to be “charged up” by a bright light

Takes no electricity – can be used on quartz, hand-wound or automatic watches

Cons

Well, it’s radioactive, so it might make your local jewelry store nervous when handling battery replacement or repairs

Doesn’t last indefinitely – Tritium has a half-life of around 12.5 years, so it will only glow half as bright after a dozen years

Some question the robustness of the glass vials that contain the tritium

What’s Best for You?

Unless you are in law enforcement or the military, you probably don’t need tritium. That’s not to say you should avoid tritium if you feel you need to have reliable illumination at all times. Now that less-expensive watches can be found with it, by all means try one out. Just be aware that it will slowly fade over a dozen years, getting less effective as time goes on.

Even electrical illumination has its place on the lower end of the scale. It sucks the juice out of a watch’s battery, but these watches tend to be so cheap you could just buy another watch when it dies. For the better watches with this kind of illumination, a few dollars for a new battery is a small price to pay.

Personally, I like high-quality luminous paint the best. With a short “charge” of light, Super-LumiNova is plenty bright for people who just need to see their watch when they wake up in the middle of the night. It won’t break, poison you, or drain a battery. If you haven’t seen how bright the glow is off a quality watch featuring this method of illumination, stop by a jewelry store and have the sales clerk demonstrate it to you. I think you’ll be impressed.