Help/advice needed for diy UV light for Amber searching

[ryansoh3]

@nofearek9

@ryansoh3

As for UV blocking glasses, check out Uvex’s goggles. (Make sure to review spec sheets.) I have the Uvex Orange for UV and blue blocking purposes, and they do a great job without breaking .

will those do the job ?

Yup, that is the one I use. Blocks out anything up to the blue frequency.

[djozz]

I have a little 400nm light also, and try it out tonight with yellow glasses blocking the purple glow. If that works so well that would be great, 400nm leds are cheap and have high power :-)

[Hestbech]

djozz

I found this, though I cant find the context of which it was uploaded (click for large image)

Can someone explain the graph to me?

nofearek9 and ryansoh3 -thanks! I also did some tests on my Oakley m-frame glasses (material is polycarbonate, called Plutonite® by Oakley). Both the clear and the yellow lens seem to block all uv-light when placed between a danish banknote and my cheap 400nm uv-light.
That fits well with the claim that polycarbonate blocks all uv-rays under 400nm

Edit:
Found the context of the amber image. Here

[nofearek9]

@ryansoh3

@nofearek9

@ryansoh3

As for UV blocking glasses, check out Uvex’s goggles. (Make sure to review spec sheets.) I have the Uvex Orange for UV and blue blocking purposes, and they do a great job without breaking .

will those do the job ?

Yup, that is the one I use. Blocks out anything up to the blue frequency.

thanks

[djozz]

I redid yesterday's images in a more proper way, I build the Nichia led into a 760mA 16340-EDC light, added a 400nm light to the scene, and made the exposures a bit more comparable. Indeed the 400nm light gave the best visible (yellow coloured, also without the yellow filter) fluorescence, so perhaps that might become the best candidate?...

It is getting quite a collection of small uv-lights now :-) :

[djozz]

Btw, the camera's white balance setting was on cfl-light this time, so the colours look a bit different from the pictures I made yesterday.

[Hestbech]

Thanks a mill!!!

No doubt that of the three 365nm the Nichia is the best. But that the Chinese 400nm is better still is a puzzle to me. But non the less, awesome that you had the time to make the test.

I already ordered a 365 Ledengin Z1, so I’ll do some field-testing with that and my cheap noname 390-400nm flashlight. If those two are good enough there is no need to get the Nichia (but i might anyway :bigsmile: )

Maybe a perfect setup would be a flashlight with both the 365nm nichia, and a good 400nm led. But I have no idea if it’s possible to do that?

-

If anyone is following this thread or finds it interesting, I found and contacted the guy who took the image I posted previously : (click for large image)

He’s got a bunch of ÜberCool uv pictures over at his Flickr Photostream

If he finds the time he’ll drop by this thread and give his take on the matter.

Cheers from Denmark

[djozz]

I happen to have one of those 400nm leds spare, and a C8 host as well. I will put it together and send it to you, and then you can have a go in the practice of searching :-)

(nothing much is lost for me here, all cheap parts that were doing nothing anyway)

[Hestbech]

Marry me!!!
:bigsmile:

[ImA4Wheelr]

This is a great thread. Lots of food for thought. Has me thinking of building a kind of semi-wide spectrum UVA light using a multi-emitter host. I already have 5 365nm emitters on the way from Simon.

Any recommendations on a budget 390 or 400nm emitters along with source?

[Hestbech]

Good to know that its helpful to other than just amber-phelia’s

Don’t know any good sources for 390 or 400nm. But I also like the idea of a wide spectrum UVA light using multiple led’s. Would hate to miss some amber because of using a wrong the wavelength

Dont know if these 380nm are any good. But it seems cheap.
1w 380nm
5w 380nm

[Confusius]

Just a weird idea here, but if 400 nm is better than 365 nm, maybe a royal blue emitter at 460 nm is even better? I have one of these in a C8 clone, and the amount of blue light from this sucker can drive you insane!

[djozz]

@Hestbech

Marry me!!! :bigsmile:

I'd love to, but that would leave behind a deranged family and a very ununderstanding girlfriend (I will not take that risk ;-) ) ..

I made the C8 and will send it tomorrow (will the return address on the envelope do?). The Ultrafire C8 host that I used has seen some abuse: the threading of the bezel is worn out (or was never good in the first place), so I closed it with duct tape. This is a good idea anyway because I made quite some effort getting the focus right (using a diagonally placed XM-centering bit around the led that I had to sand very thin to get the reflector in the right depth, also put an o-ring under the pill to let the pill thread in just a bit less deep to make the reflector push hard enough on the ledboard), opening up the head will spoil that and it then has to be re-done (=no rocket science, but why spoil it?). The light is direct drive, no driver, just direct wiring through from the battery to the led, I used an old version BLF17FET-board as a contact plate for the battery. This led runs on between 1.5A and 1.8A like that which is reasonably optimal for this led (thread from some time ago about the led here). So the runtime will be a bit under 2hrs on a good capacity 18650 battery.

So it looks a bit amateuristic with the tape, but it is fully functional, and I think quite robust and waterproof as well. Actually a 400nm thrower is more fun than I thought it would be :cool: .

Pics or it didn't happen :-) :

[djozz]

For 400nm light (and other uv-lights) I have (my brand is Bollé) safety goggles with amber coloured glasses, it blocks uv and gets rid of most purple/blue, but still the glasses are only slightly coloured so you don't loose much light. Similar to this one:

[Hestbech]

Lol! - will save the marriage proposal for my girlfriend then
Yes the return address will do just fine.

So it looks a bit amateuristic with the tape

Looks fantastic! I’ll make sure to keep my hands of the tape. Time, tear and wear just makes it authentic. Kind of like collecting amber. You find a piece, and your imagination wanders. Well mine does anyway. Hell, it was once a “living thing” (originating from a tree) 40 million years ago. And I’m the first human EVER to pick it up. The last thing it “saw” could have been a T-rex! -or a mosquito. Have a couple of pieces containing insects myself (not collected by me though)

Confusius -that could possibly be true! -that would make the claims that amber is fluorescent from 320-380nm even more puzzling.

But thanks to djozz’ tests and this page (I really hope Bob who took the images drops by this thread), I think we are closing in on THE truth about amber. The Goldilocks zone must be somewhere between 365-400nm

[Hestbech]

djozz I’ve got bot a pair of Oakley M-frame with yellow and clear lenses. And a pair of yellow tinted safety glasses from the danish army. So I’m ready for battle

The safety glasses might actually be a good idea, as unexploded mines from WW2 from time to time appears in the areas where I go amber-hunting :-p

[ImA4Wheelr]

Thanks for the info an link Hestbech.

[alpg88]

@Jubeldum

As for mounting a LZ1 on DTP copper, djozz is a master at modding a MCPCB. Doing something like this is like childs play to him.

nope, lz1, just like the rest of ledengin leds, have totaly different foot print, you can’t mod xml\xpg star for it. why even bother, they are sold mounted on correct stars.

[Jubeldum]

@alpg88

@Jubeldum

As for mounting a LZ1 on DTP copper, djozz is a master at modding a MCPCB. Doing something like this is like childs play to him.

nope, lz1, just like the rest of ledengin leds, have totaly different foot print, you can’t mod xml\xpg star for it. why even bother, they are sold mounted on correct stars.

Is that so? So you are saying there is no way to be able to modify a XML or XML Color MCPCB to mount a LZ1 so you can have DTP?
https://budgetlightforum.com/t/-/24011?page=2#comment-674651

Is it also impossible to modify a XML MCPCB to be a XML Color MCPCB?
https://budgetlightforum.com/t/-/26139

[Hestbech]

Nice mods

I got a reply from Bob who took the pictures linked to earlier:

@Robert Fosbury

I have a number of other observations of amber. Try looking at: Search: amber | Flickr.

I will look at your thread and give you a considered answer a bit later. My immediate answer would be to use an LED-based (flashlight) lamp around 365 - 380nm BUT you have to add a visible-blocking filter to remove any residual visible light since these LEDs have a long tail of emission spreading over the visible spectrum. I use a Schott UG2 glass filter which works perfectly. I got a whole set of these flashlights from one of my PhD students from China where he can buy them for almost nothing - they sell them for searching houses for pet urine!

More later.

…

Me: Amazing images! I’m trying to figure out your graphs. Will have to do some research on that

The plots I post on flickr are of two types:

1. Fluoresence - these show the power per unit wavelength emitted from the material when it is illuminated by an excitation source (usually UV)

2. Transmission - these show the fraction of the incoming light transmitted by the sample at each wavelength (unitless)

Baltic amber generally fluoresces a pale ‘powder’ blue. The fluorescence is emitted at the surface and looks like a fine coating of blue dust. The best way of seeing this is to use the type of LED lamp I mentioned in my last email. There is no particular point in trying to get LEDs at shorter wavelengths: they emit much less power, they are expensive and they have short lifetimes. 365-380nm is fine as long as you block the visible light with a filter as I suggested.

Me: I recently started collecting amber at the western coast of Denmark. So any tips on the wavelength would be fantastic.

Blue amber - from the Dominican Republic or from Sumatra has different fluorescence properties and is very interesting for a number of reasons which are explained in my flickr posts.

All the best, Bob