Wide spectrum UV light?

norbert77

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Hello all, I was reading an article on insects and some of them have UV markings that show up under different wavelengths. Is there such a light that has multiple wavelengths?
 
Greetings!

I know such lights exists. I had a StreamLight TwinTask back in the day, that offered both 365 nm and 395 nm, plus white light. But that one has long since been retired.

Currently, I only have separate 365 nm and 395 nm (that I thought was 365 nm...), like Sofirn SF16 and SF15. SF16 (365 nm) has a UV-filter, but the SF15 does not, and requires yellow UV-glasses for best visibility.

Your best bet for a quality light would be something custom. And I frequently see suggestions of "contact Hank" (Hank Wang, at Emisar) being posted for such lights. Contact email at the bottom.

I'm guessing something like a dual-channel mule (form factor / battery as desired - DW4, D4K etc.), with 365 nm on one channel and 395 nm on the other, and a UV-filter.

Or a triple-channel, with 365 nm + 395 nm + something hCRI. That could look something like this:


I own several Emisar lights, including a couple custom ones. So...contact Hank, and see what he can do for you. :)
It will likely be quite expensive though.

For cheaper options, I would suggest separate lights, like something from Convoy with 365 nm.

...and since most cheap lights are 395 nm anyway, so you can get those almost anywhere.
 
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Hello all, I was reading an article on insects and some of them have UV markings that show up under different wavelengths. Is there such a light that has multiple wavelengths?
There are combination longwave/shortwave UV lights that have either two fluorescent tubes or a single "split" tube that produces both 365nm UVA and 254nm UVC. They're sold as mineral prospecting lights. I've never seen a tri-band LW/MW/SW UV light, although it's certain;y possible to produce one.

There are a wide range of UV LEDs available now, so this could theoretically be built as a solid state tri-band lamp., but shortwave UV LEDs are still fairly weak.
 
Had a lot of time to follow those suggestions, I think the 365 and 395 are the range I need. I saw some things like orange filters, how do those work? Block the light emitted, or does one need glasses?
 
I saw some things like orange filters, how do those work? Block the light emitted, or does one need glasses?
I had to look this up myself awhile back, and do some experimentation.

TL;DR:
A light without a filter also emits blue light that decreases the UV-effect. Use yellow UV safety glasses to block the blue light from hitting your eyes.
A filter on the light blocks the blue light emitted from the LED, and only lets through the UV wavelength. Use clear UV safety glasses for eye protection.

A filter on the light or wearing yellow glasses basically does the same thing, which is blocking blue light.

If you get a UV-light that comes with a UV-filter, you do not need yellow glasses (other than the recommended clear UV-protective safety glasses).
But if the light does not have a filter, yellow glasses reduces the amount of blue light that hits your eye, and you will see the UV-effect better.

I use "3M Secure fit 3700" UV safetly glasses, with clear or yellow glass, depending on whether the light has a filter or not.
Using yellow glasses with a UV-light with a filter will only reduce the perceived effect of the UV.
 
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I had to look this up myself awhile back, and do some experimentation.

TL;DR:
A light without a filter also emits blue light that decreases the UV-effect. Use yellow UV safety glasses to block the blue light from hitting your eyes.
A filter on the light blocks the blue light emitted from the LED, and only lets through the UV wavelength. Use clear UV safety glasses for eye protection.

A filter on the light or wearing yellow glasses basically does the same thing, which is blocking blue light.

If you get a UV-light that comes with a UV-filter, you do not need yellow glasses (other than the recommended clear UV-protective safety glasses).
But if the light does not have a filter, yellow glasses reduces the amount of blue light that hits your eye, and you will see the UV-effect better.

I use "3M Secure fit 3700" UV safetly glasses, with clear or yellow glass, depending on whether the light has a filter or not.
Using yellow glasses with a UV-light with a filter will only reduce the perceived effect of the UV.
Isn't the filter just to reduce eye damage?
 
Ok, better yet, how would I go about getting the best footage from a drone? I'm interested in the fluorescent quality of the 390-ish wavelength, if I could send a drone way up into the canopy of a tree would the drone camera see the fluorescence?
 
Isn't the filter just to reduce eye damage?
If the filter on the flashlight were to protect against eye damage, then it would have to limit the UV-output. Which would rather defeat the purpose of a UV-light.

So no, unless there is something I have totally missed, the filter (like a ZWB2) blocks every wavelength from the LED other than UV. So please use UV-protective glasses when using any UV-light. UVA is probably safe for your eyes, but why take any chances.
 
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If a lost item doesn't already contain a fluorescent pigment, it won't fluoresce under any wavelength. However if it's a certain color (let's say a lost phone in an orange case), searching for it with all of the lights turned off except for an orange LED light, it will be more reflective than it's surroundings, which will make it jump out from the background.

Once you find the lost item, you can always mark it with invisible UV ink (except for the optics) and then you will have a better chance of seeing it with a black light.
 
it would be a purple phone. I was hoping the screen would reflect somehow
Purple is a combination of red and blue. I suspect a blue led might make it stand out against the background, but blue will also fluoresce some things which would add to the visual clutter. If that happens, try a red LED instead.
 
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