Light Charging Tritium Lume?

[HogwldFLTR]

I replaced the dial on my 1803 a while ago due to a scratch through the applied crown and noticed that although the old one would still faintly glow in the dark, the replacement dial was always dark. I assumed this was due to the age of the tritium in the markers. The hands still maintain a faint glow as they weren't replaced or were Luminova replacement hands. The other night while walking the dogs I held the flash light to the face of the watch and low and behold I was rewarded with brightly glowing hands and markers. Looking around the web I was able to find at least one citation that said Tritium charged paint will glow in the dark if charged by light. Any one else experience this? Sorry, no photo of the glow results.

[sahcivan]

I do it all the time messing with my BLNR and iphone

[HogwldFLTR]

Originally Posted by sahcivan

I do it all the time messing with my BLNR and iphone

BLNR isn't tritium it's SuperLuminova however; discussing the ability of Tritium markers to be light charged...

[Valkyrie]

If paint glows after being charged with light it has nothing to do with the presence or absence of tritium. If tritium is present, the paints previously used by watchmakers will glow continuously until the tritium decays away (half life of about 12 years). The radioactive decay of the tritium is what causes the paint to glow and charging with light does nothing to speed up or slow down the rate of decay of the tritium.

[Rolex fan 61]

I had tritium markers on a non - rolex divers watch, the watch was 20 years old and I could still clearly see the markers and hands all through the night.

[Tools]

Originally Posted by HogwldFLTR

. . . Looking around the web I was able to find at least one citation that said Tritium charged paint will glow in the dark if charged by light. Any one else experience this? Sorry, no photo of the glow results.

. . .

No, it won't. Tritium does not glow, it is the radioactive properties of tritium that keep the phosphorescent paint glowing at all times. When the tritium no longer emits it's beta-ray then all you have left is the very under-powered paint.

Some phosphorescent (radio-luminescent) paint will glow faintly when hit by light for a very short time; you cannot re-charge tritium.. But, unless it is photo-luminescent paint, like Luminova, it is a waste of effort.

[RGAmos]

I do not know how tritium is used in watches, but some gun night-sights have small glass modules filed with tritium. Of course tritium glows, it is the result of the radioactive decay.

[Valkyrie]

Originally Posted by RGAmos

I do not know how tritium is used in watches, but some gun night-sights have small glass modules filed with tritium. Of course tritium glows, it is the result of the radioactive decay.

Tools is correct, tritium alone does not glow. Tritium is a beta emitter and the radioactive decay does not produce visible light. The internal surface of the glass modules you refer to are coated with a phosphor that is excited by the beta particles from the decay of the tritium and produces the visible light that is seen.

[HogwldFLTR]

Originally Posted by Tools

No, it won't. Tritium does not glow, it is the radioactive properties of tritium that keep the phosphorescent paint glowing at all times. When the tritium no longer emits it's beta-ray then all you have left is the very under-powered paint.

Some phosphorescent (radio-luminescent) paint will glow faintly when hit by light for a very short time; you cannot re-charge tritium.. But, unless it is photo-luminescent paint, like Luminova, it is a waste of effort.

I believe that the statement was quite clear that it was not the tritium that was glowing. It clearly is not Luminova as the glow duration is brief. Nothing was said about recharging tritium either. Please explain what is going on if you know. Although your description may be accurate and enlightening for some, as a rebuke it is inappropriate. Are you really calling to question the credibility of what I'm reporting? Not wise to question something that is real and verifiable. The most obvious answer to the mechanistic question is that there is some photo luminescent quality to the paint that was used in the markers.

[RGAmos]

Originally Posted by Valkyrie

Tools is correct, tritium alone does not glow. Tritium is a beta emitter and the radioactive decay does not produce visible light. The internal surface of the glass modules you refer to are coated with a phosphor that is excited by the beta particles from the decay of the tritium and produces the visible light that is seen.

Learn something every day. Thanks.

[Tools]

Originally Posted by HogwldFLTR

I believe that the statement was quite clear that it was not the tritium that was glowing. It clearly is not Luminova as the glow duration is brief. Nothing was said about recharging tritium either. Please explain what is going on if you know. Although your description may be accurate and enlightening for some, as a rebuke it is inappropriate. Are you really calling to question the credibility of what I'm reporting? Not wise to question something that is real and verifiable. The most obvious answer to the mechanistic question is that there is some photo luminescent quality to the paint that was used in the markers.

Rebuke

Providing the members with information is something I frequently do within threads.

I will be careful not to do so in future threads of yours..

[77T]

The paint itself has phosphorescent properties that tritium causes to glow. Once the tritium has decayed it leaves the user with phosphorous paint and it may be possible that it strong light could make it glow.
I had a GMT with a depleted T Dial, but even when I used a strong light I couldn't make the dial glow.

[Abdullah71601]

Originally Posted by 77T

The paint itself has phosphorescent properties that tritium causes to glow. Once the tritium has decayed it leaves the user with phosphorous paint and it may be possible that it strong light could make it glow.
I had a GMT with a depleted T Dial, but even when I used a strong light I couldn't make the dial glow.

Agree The tritium is the flashlight, if you will, until it has decayed to the point that it doesn't generate enough energy to illuminate the paint.

The phosphorescent chemical properties of paints also decay over time. Some paint charged with an external source will glow brighter or longer than others. The OPs experience may be related to differences in the paint itself. The tritium is long dead and is merely a distraction in the conversation.

[HogwldFLTR]

Originally Posted by Tools

Rebuke

Providing the members with information is something I frequently do within threads.

I will be careful not to do so in future threads of yours..

Larry, it certainly felt like a rebuke correcting things that didn't need correcting. It's fine providing information but not suggesting that I implied things I didn't which is how I perceived it. You're more than welcome to add from your wealth of knowledge just keep me out of the cross hairs if I don't deserve to be in them. If not adding to threads I've started is the best you can do, then so be it. I believe you understand my point. Enough said.

[Andad]

Well Lee,

I have read your posts and Larry's posts on this thread and can only suggest you lighten up....

I have also just dug an old Trit dialled watch out of the box and left it in the sun for ten minutes.

In the a dark I saw nothing.....not even a slight momentary flicker....as I expected.

Could be the phos paint gave out before the Trit did and other results may vary but I think you are overreacting.

[HogwldFLTR]

Originally Posted by directioneng

Well Lee,

I have read your posts and Larry's posts on this thread and can only suggest you lighten up....

I just dug an old Trit dialled watch out of the box and left it in the sun for ten minutes.

In the a dark I saw nothing.....not even a slight momentary flicker....as I expected.

Charged by my iPhone light. Glow lasts only for a few seconds on the hour markers. Actually hard to turn off the iPhone light and get the photo taken before the glow fades. I'm totally chill fwiw.

[Abdullah71601]

Originally Posted by HogwldFLTR

Charged by my iPhone light. Glow lasts only for a few seconds on the hour markers. Actually hard to turn off the iPhone light and get the photo taken before the glow fades. I'm totally chill fwiw.

I think the phosphorescence in the marker paint is toast. As has been stated, it doesn't last forever either (look at radium dials). Are these luminova service hands?

[HogwldFLTR]

Originally Posted by Abdullah71601

I think the phosphorescence in the marker paint is toast. As has been stated, it doesn't last forever either (look at radium dials). Are these luminova service hands?

Absolutely agree that the markers are useless since they only charge for seconds but that was my point that they do charge. Pretty certain that the hands are replacements but not on my shift with the watch. I just had no idea that they'd respond to light at all. But as was pointed out; there really is no value that this function adds to the watch. It's just and observation and perhaps distinguishes different tritium paints used by Rolex.

[dreamcar88]

The iphone light worked for couple seconds.. i didnt even know my dj had lume. I got my first winder with a led light and on the way back to bed i saw a faint lume. Wish it lasted longer

[Abdullah71601]

Originally Posted by HogwldFLTR

Absolutely agree that the markers are useless since they only charge for seconds but that was my point that they do charge. Pretty certain that the hands are replacements but not on my shift with the watch. I just had no idea that they'd respond to light at all. But as was pointed out; there really is no value that this function adds to the watch. It's just and observation and perhaps distinguishes different tritium paints used by Rolex.

Have you looked at the markers with a loupe under a black light? Different spent paints will fluoresce differently. If you're curious about seemingly insignificant differences in dials, this is one that can produce some mildly useful information.

[Dirt]

Originally Posted by HogwldFLTR

I believe that the statement was quite clear that it was not the tritium that was glowing. It clearly is not Luminova as the glow duration is brief. Nothing was said about recharging tritium either. Please explain what is going on if you know. Although your description may be accurate and enlightening for some, as a rebuke it is inappropriate. Are you really calling to question the credibility of what I'm reporting? Not wise to question something that is real and verifiable. The most obvious answer to the mechanistic question is that there is some photo luminescent quality to the paint that was used in the markers.

I believe I can confirm your experience with your Tritium watch dial.
My earliest experience with older Rolex dials marked as having Tritium would be for them to glow brighter immediately after going into a dark space when charged by a bright light source like broad daylight.
The results of the exercise were 100% repeatable, but the increased glow is very short lived.
It was back the days before I ever had a Luminova dialed Rolex watch.
I didn't know why this occurred as the widely accepted theory behind the luminous glow of Tritium paint generally would not support this phenomenon.

However, out of curiosity I did ask your question on a couple of other watch forums back in the day when the issue was more fresh and not long after the transition to Luminova based compounds.
The result was, a few very knowledgeable respondents stated that the light source used to charge the Tritium compound causes the electrons in the paint to "excite".
Their explanation would go on to elaborate in that the resulting excitation makes the electrons jump up above the surface thereby briefly increasing the glow.
I'm no nuclear physicist but it certainly seemed plausible to me and supported my/our observations.

As an aside.
I still have one of my dials that used to behave in the very manner you describe which is dated back to about 1996-1997 marked as Tritium, which was left over from a dial and hands swap.

Interesting stuff

[Dirt]

Originally Posted by Abdullah71601

Have you looked at the markers with a loupe under a black light? Different spent paints will fluoresce differently. If you're curious about seemingly insignificant differences in dials, this is one that can produce some mildly useful information.

Yes.
I have seen one Rolex watch dial marked as having a Luminova dial actually glow Violet.
Back then I just assumed it was because of the nature of the new Luminova lume.

However, I have never seen the phenomenon again under much the same conditions with any of my Superluminova dials or Chromalight dials.
I just assumed this was because the Luminova dial was more white or perhaps made differently with the result it glowed like white underwear when under artificial UV light. Very pretty.

Does this correlate with your observations?

[Dirt]

Originally Posted by Abdullah71601

Agree The tritium is the flashlight, if you will, until it has decayed to the point that it doesn't generate enough energy to illuminate the paint.

The phosphorescent chemical properties of paints also decay over time. Some paint charged with an external source will glow brighter or longer than others. The OPs experience may be related to differences in the paint itself. The tritium is long dead and is merely a distraction in the conversation.

Great stuff

[Abdullah71601]

Originally Posted by Dirt

Yes.
I have seen one Rolex watch dial marked as having a Luminova dial actually glow Violet.
Back then I just assumed it was because of the nature of the new Luminova lume.

However, I have never seen the phenomenon again under much the same conditions with any of my Superluminova dials or Chromalight dials.
I just assumed this was because the Luminova dial was more white or perhaps made differently with the result it glowed like white underwear when under artificial UV light. Very pretty.

Does this correlate with your observations?

Most of the old phosphor was copper activated zinc sulfide. It didn't need to hold a charge because it had a radioactive source integrated into it, and worked fine for that purpose. The radiation degrades the chemical phosphorescence over time, hence you don't see much from a radium dial even though there is still more than enough radium there to illuminate it. And it won't hold a charge from a light source. IIRC, you'll see green bits under black light from this paint.

Luminova uses strontium aluminate, which can be adjusted chemically to emit different colors of light based on various treatments to the compound. It's also built to hold a charge for awhile once the source is removed. It should look white under black light.

[Dirt]

Originally Posted by Abdullah71601

Most of the old phosphor was copper activated zinc sulfide. It didn't need to hold a charge because it had a radioactive source integrated into it, and worked fine for that purpose. The radiation degrades the chemical phosphorescence over time, hence you don't see much from a radium dial even though there is still more than enough radium there to illuminate it. And it won't hold a charge from a light source. IIRC, you'll see green bits under black light from this paint.

Luminova uses strontium aluminate, which can be adjusted chemically to emit different colors of light based on various treatments to the compound. It's also built to hold a charge for awhile once the source is removed. It should look white under black light.

Thanks, very informative

Quite frankly the Violet glow when under the Black light was really amazing.
At the time, I actually didn't realize it was under a Black light until I saw the pretty colour of the lume on the dial.
It's never been replicated since with any other watch.

I suppose I shall put it down to the stark white of the pigment reflecting the Ultra Violet light. Just like white underwear does.

[petereoin]

My 5513 '68 glows very similar to HogwldFLTR, but this is without having to power it by a light source.

It glows very dimly in a very dark room after my eyes are adjusted to the darkness.