Looking for an UV light.

Any recommendations? Ive found several threads that are over a year old, some up to 4 yrs.

I am hoping to find a fairly cheap (< 30 dollars) UV light that is able to light up stains (CSI-like) and currency.

That means it needs to be 385nm wavelength or better. The 375s would be great.

Where would be the best place to get one? Unfortunately lighthound is out of stock on theirs that has a CPF review. Ive seen a few others but I am a bit dubious about the wavelenght, many of which are 395-400nm.

I understand that for 30 bucks you arent gonna get something incredible, but ive found several 375-385nm led lights out there. So I believe it is possible, but I am just looking for a reputable place to get one, or advice on a specific one to get.

Thanks!

i buy my 385nm on e bay from this guy
that exact light is really 385.
there are plenty of low quality 400+nm that are misrepresented, and claimed to have 380nm, but i've tried many before i found out that for $20 or so i can only get 385nm there, it is 9leds 3aaa light.
compared to other uv this one emits a lot less visible light, and on my test subject (Jamaican $100 bill) reveals a lot more fluorescing details than with other uv lights.

I did a lot of research (read a lot of threads on cpf and other forums) about UV lights, and it appears that the Arc-UV is the best light out there with a 375nm wavelength. It is costly, and on my "wishlist", but other lights are either large and require more batteries, or take non-AA/AAA batteries.

I have had great luck with UV Inova X5. I use it to check ID's and other things. Its a 395nm one that runs for 20 hours on one set of 123's. Its solid as a rock, no plastic at all. It doesnt meet some of your requirements but it will most likely be the only/last UV light you have to buy.

http://www.brightguy.com/products/Inova_X5_UV_(Ultra_Violet).php

I purchased a drop in P60 UV lamp from battery junction for about $20 plus shipping. Worth a try if you have a host. - HDSFAN

Here's a pretty good thread on the topic on the first page of the LED flashlights subforum.

I have a Streamlight Twin-Task 51010 and its one of the better UV lights out there compared to the cheap showerhead lights. It has three modes:3 X 375nm led's, 3 X 375nm and 3 X 390nm led's, and a xenon bi-pin lamp. Its a little bit more expensive than your $30 budget at $42, but the extra $12 is well worth it. Top it off with a lifetime warranty from streamlight and its money well spent.

Whatever UV light you decide to get make sure to pickup some UV safety glasses. You can get them for as little as $5.

This one is pretty good for a general purpose UV light.
http://www.batteryjunction.com/lri-proton-pro-pruv.html

Thanks for the replies. I am definitely reading them!

After much searching, here is my conclusion:

I am going to buy a 6 dollar fluorescent tube light!
(example)
http://www.blacklight.com/items/CODE10

Why?

It turns out that these things have 4 watts of power, and Flu lights are pretty close to LED efficiency. They are at least half as good, so this corresponds to a 2.5 Watt LED light.

Well, most LED UV lights use 5mm LEDs that produce MILLIwatts of power. usually 10mW per LED. Your power output is way less than 2.5 watts.

There are a handful of lights that use UV power LEDs, but these aren't really made anymore and aren't super efficient.


Also, 400nm LEDs are cheap to make, but 365nm wavelength ones are not. Hence, most LED UV lights produce lots of Purple but not so much actual UV.
Turns out that fluorescent lights are made with a peak of 365nm, which is perfect for the cooler uses of UV. Whereas most LEDs will only be good for viewing some hidden stuff at extremely short range.

There are some good pictures of 365nm vs 375, 385, 395 wavelength that show how much better 365 is at making things glow, vs the higher wavelengths.


While I don't like the form factor of the fluorescent and would prefer flashlight look, it doesn't really seem to be feasible for now if you want a pretty decent UV output. This is one area where LED technology stays old and stagnant and isn't even coming close to catching up. Heck, as mentioned Cree doesn't even MAKE UV emitters anymore...

joe1512 said:

Any recommendations? Ive found several threads that are over a year old, some up to 4 yrs.

I am hoping to find a fairly cheap (< 30 dollars) UV light that is able to light up stains (CSI-like) and currency.

That means it needs to be 385nm wavelength or better. The 375s would be great.

Where would be the best place to get one? Unfortunately lighthound is out of stock on theirs that has a CPF review. Ive seen a few others but I am a bit dubious about the wavelenght, many of which are 395-400nm.

I understand that for 30 bucks you arent gonna get something incredible, but ive found several 375-385nm led lights out there. So I believe it is possible, but I am just looking for a reputable place to get one, or advice on a specific one to get.

Thanks!

Click to expand...

I just went through a rash of UV light purposes, so I can offer my experiences up for you to judge. I bought them for 1 purpose only - finding scorpions, and killing them with a long screwdriver. :twothumbs

1. Streamlight Twin Task 3C. Dual wavelength version (black anodized), 365nm & 390nm. Observations: heavy. low visible light thrown (could be good for your situation - but for mine, I am walking around outside and need some visible purple light thrown to see where or what I am walking into). all currencies I have (newer USD, Euro, Sing, GBP, MYR, HKD, Indonesia) glow under this light. UV throw is not great (~10ft for scorpions). Reflector not centered perfectly to the UV LEDs, and reflector sits too high above the 365nm LEDs.

2. Cheap-o DX Ultrafire WF-501B 3W UV dropin. pretty awesome for scorpions. excellent UV throw (~20ft for scorpions) and good visible light sidespill to see where you are walking. does output a good amount of heat, so continuous use MAY be a problem. I use it for approx 30 mins per session, and it's close to uncomfortable levels. hit or miss quality with the host, you can google here for threads ad naseum on that topic.... Won't light up some currencies (Sing, Indonesia). Who knows the wavelength, it's DX afterall....

3. Walmart plugin AC black light tube. Awesome! lights up the entire backyard, can find the ******* scorpions very easily. cons. hard to carry around while keeping my stabbing hand free.

Dont know if that helps, but at least you can laugh at someone prowling around the yard at night with a 100ft extension cord holding a blacklight from Walmart and a 1ft long screwdriver - all for killing scorpions.

Cheers!