What is the purpose of UV flashlights?

Monocrom

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Two purposes:
1- Check for Scorpions before going to bed. If you have a family member serving in a desert, be sure the next care-package to that soldier includings a small keychain-sized coin-cell UV light.

2- Checking the bed for "Adult" stains before sleeping in a motel room.

(Sometimes ignorance is best.)
 

alpg88

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Apr 19, 2005
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Can you get a video of that? Sounds like fun but who cleans it up?
When we do it in summer time i could, balloons do not really pop when it is cold. just slowly deflate. Whoever shoots the worst.
 

fulee9999

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Mar 3, 2021
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I mostly use UV to check wall painting to try and see
1, if the previous layers, glues and whatnot has been properly removed before priming
2, if the coverage is actually good and the primer is not showing through the color anywhere
 

Monocrom

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I mostly use UV to check wall painting to try and see
1, if the previous layers, glues and whatnot has been properly removed before priming
2, if the coverage is actually good and the primer is not showing through the color anywhere
Thanks for reminding me....

3- If you have a UV pen, you can write or draw on wall-paper. Image or message will be unseen unless someone uses a UV flashlight on the walls.
 

alpg88

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airsoft teams do this all the time, uv chalk/paint markings, my friend is heavy into it, came to me for uv flashlights.
 

fulee9999

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Thanks for reminding me....

3- If you have a UV pen, you can write or draw on wall-paper. Image or message will be unseen unless someone uses a UV flashlight on the walls.

lol I should start leaving 4-8-15-16-23-42 written on the walls everywhere :D

1707439034977.png
 

PhotonWrangler

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Curing UV adhesives, collecting fluorescent minerals, inspecting for microscopic cracks in materials using UV dye, looking for signs of water damage, checking for lice, producing spooky effects for Halloween decorations, many more.
 

hamhanded

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There's a hidden strip in $100 bills that will fluoresce red orange under 365nm but not 395nm.
 

chaosdsm

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Florida
LOTS of uses for UV lights here are just a few....

> Find & identify minerals
> Finding scorpions
> Plant identification... certain plants glow certain colors under UV light, as does some wood.
> Verification of many legal documents, passports, currency, etc....
> Detecting counterfeits, repairs, & modifications - art, currency, legal documents.
> Leave & find secret messages written in UV inks - invisible under normal lighting
> Finding stains of ALL kinds
> Detecting virus & bacteria
> Detecting bio-matter of any kind
> Finding leaks with UV dye in air conditioning systems
> Finding leaks in potable water systems using Riboflavin
> Parties. Add some Riboflavin (vitamin B2) to drinks and it will glow under UV & so will your urine afterwords :devilish:
> Telling me it's a good thing I brought my own sheets, blankets, pillows, & plastic sheeting to the motel.....
 

PhotonWrangler

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Joined
Oct 19, 2003
Messages
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In a handbasket
LOTS of uses for UV lights here are just a few....

> Find & identify minerals
> Finding scorpions
> Plant identification... certain plants glow certain colors under UV light, as does some wood.
> Verification of many legal documents, passports, currency, etc....
> Detecting counterfeits, repairs, & modifications - art, currency, legal documents.
> Leave & find secret messages written in UV inks - invisible under normal lighting
> Finding stains of ALL kinds
> Detecting virus & bacteria
> Detecting bio-matter of any kind
> Finding leaks with UV dye in air conditioning systems
> Finding leaks in potable water systems using Riboflavin
> Parties. Add some Riboflavin (vitamin B2) to drinks and it will glow under UV & so will your urine afterwords :devilish:
> Telling me it's a good thing I brought my own sheets, blankets, pillows, & plastic sheeting to the motel.....
UV tracer paste and UV ink for identifying a nearby thief or mischief maker. They used to coat the handles of public fire alarm pull boxes with UV tracer paste. If a false alarm was pulled, the firemen would check the hands of nearby kids for glowing fingers.
 

Galane

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Jul 6, 2022
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Location
Idaho
Supposedly if a person's skin has Blaschko lines due to cutaneous chimerism, the lines may be visible with UV light. However, I've yet to see a single UV photograph showing the lines, nor have I read any article making that claim which specifies the UV wavelength that makes the lines visible.

UV light can show uneven spots and subsurface skin damage from long term sunlight exposure. But again, no article I've read showing such images bothers to specify the wavelength. Whatever UV wavelength is used, nearly everyone has freckles visible with it.

The lines can visibly manifest through various skin conditions to which one set of skin cells is immune or resistant. In a few rare cases of people whose parents have very different skin colors, the embryonic stem cell DNA that went into the skin went half this way and half that way, rather than mixing well or one parent's skin DNA dominating. So they came out looking like chocolate vanilla swirl. In the "I am my own twin" documentary an old photo was shown of a person with skin that was half brown and half white, in alternating blocks left and right with straight edges, and a dividing line straight up their front. The head was blurred or cropped off so one couldn't tell if their face was half and half. The person's back wasn't shown. The photo looked like it was probably from the late 18th or early 20th century.

A woman named Taylor Muhl is a current example of cutaneous chimerism where her left side from mid breast down has skin with a ruddy complexion, with a perfectly straight vertical dividing line up her front. On her back the division is swirly. She posted some bikini pics a while back to show that. But in her case the chimerism is literally bone deep. She has two different blood types circulating thanks to the different bone marrow DNA in her left side bones. The immune systems of the different parts of her body tend to fight so she frequently has auto-immune symptoms. Fortunately the DNA mashup didn't result in skeletal size differences between left and right.
 
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