homemade aspheric lens kitchen funnel attachment thingo for Fenix L2D-CE

Hi everyone.
I'd better apologise straight away for the stupid thread title - thought it would attract some viewers.

Anyway, yesterday I got a 45mm diameter, 30mm focal length aspheric lens in the mail from surplusshed. I've now made an attachment (out of a small kitchen funnel, a bit of plastic, sticky tape and superglue) for my Fenix L2d. (It looks a bit weird, but it fits.)
Sorry, I can't post attachments for some reason, but I'll try to describe the result. Basically, it throws as far with the lens in low mode as without the lens in turbo; looks almost like a laser beam where it comes out of the lens.
It's a bit hard to guess, but I think the beam probably spreads about 60-70 cm over 15 or 20 metres. A fair bit, not super focused, but hugely different to the normal beam pattern.

Overall, it's definately worth trying . There are also some 50 and 60 cm focal length lenses where I got this, which would increase the throw another 2 or 3 times!

very interesting. your description is quite clear. i'll have to give this a go with a spare planoconvex lens that's 52mm dia, 35mm focal length and a spare funnel. that lens is spare for a couple of aspheric Mags+TerraLux lights.

many thanks for sharing your idea.

Cool, I've been playing with 52mm (PL1028?) from Surplus Shed. Looks great on a 4D mag - ok with Xenon, much better with MagLed.

I've also tried the lens with a G2 Xenon and UF Cree - too much light is lost to be very bright. Now looking for inexpensive 26-28mm PCX with ~15 - 25mm focal length.

Great thread title! This sounds fun, too. And when you've got your post count up a bit, you will be able to post photos and let us see some beamshots...

Jaz said:

Hi everyone.
I'd better apologise straight away for the stupid thread title - thought it would attract some viewers.

Anyway, yesterday I got a 45mm diameter, 30mm focal length aspheric lens in the mail from surplusshed. I've now made an attachment (out of a small kitchen funnel, a bit of plastic, sticky tape and superglue) for my Fenix L2d. (It looks a bit weird, but it fits.)
Sorry, I can't post attachments for some reason, but I'll try to describe the result. Basically, it throws as far with the lens in low mode as without the lens in turbo; looks almost like a laser beam where it comes out of the lens.
It's a bit hard to guess, but I think the beam probably spreads about 60-70 cm over 15 or 20 metres. A fair bit, not super focused, but hugely different to the normal beam pattern.

Overall, it's definately worth trying . There are also some 50 and 60 cm focal length lenses where I got this, which would increase the throw another 2 or 3 times!

Click to expand...

oh, i forgot to mention in my first reply to you, that the proper technical term is NOT "Thingo", it's "Thingy".


Great idea you came up with. Good for you. Thanks again for sharing it.

thingamajabob!

Re: homemade aspheric lens kitchen funnel attachment thingo thingy thingamajobob!

Thanks for showing interest in the idea everyone. Let us know how it goes, half-watt.

chesterqw said:

thingamajabob!

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That's the technical term, is it? All right then, i've changed the thread title.

Edit: oops, that's just for this post. Didn't know you could do that.


By the way, I'd guess that the lux reading with the lens would be somewhere between 65 000 and 100 000, but I don't have the equipment so can't test it.

LOL @ thingy...thingamabob...thingamajig...and not limited to thingamahbobby/thingamajiggy.

LOL, it is a very accurate and descriptive word. We can all tell immediately EXACTLY what it is.

I live "just a pieceways down the road" (like they say in Pennsylvania Dutch country) from Surplus Shed. They just opened a retail store in Reading PA at the Fairgrounds Square Mall (it's worth dropping in if you're ever in the area).

I stopped by the store last weekend and was chatting with one of the guys. They're sort of amazed at how many lenses they sell that say "CPF Forums" in the comments field. :huh:

Anyway... we were talking about achromats. Using multiple lenses to focus a flashlight even further than any single lens can. The employee (I forgot his name but you may see him here sometime as "SurplusShedGuy") was telling me about something new they're going to have soon.

They're having black anodized, aluminum, machined tubes made for them (if I remember right it's about 4-6" long). The tube will come with universal adapters so you can attach the end to just about anything (camera/flashlight/whatever you want to use it for). It will also have retaining rings so you can put 3 lenses in it. So if you wanted to make your Malkoff Drop-in into a light saber... it should be easy to do.

I saw the test samples and they were nice (well, as nice as a threaded aluminum tube can be). They're supposed to be up for sale (on the website) very shortly.

Thought you guys would like to know. :candle:

Jaz said:

Hi everyone.

Sorry, I can't post attachments for some reason, but I'll try to describe the result.

Click to expand...

You can upload your photos to a hosting site and then post the linked pic here. That is what I do and it works great. I use http://www.Photobucket.com . Works great and is free. You can also put videos up on there.

He needs to get his post count up before he can post pics. I think you have to have >30 posts.

mrmike said:

. . . They're having black anodized, aluminum, machined tubes made for them . . .
Thought you guys would like to know. :candle:

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Yes! Thanks for passing this along! I was just looking for these the other day. I stuck a DCX in my LumaHunter M1 Tactical and a ring/tube would have helped... Going aspherical is awesome btw, the wow-factor is huge.

Thanks

You can upload your photos to a hosting site and then post the linked pic here. That is what I do and it works great. I use http://www.Photobucket.com . Works great and is free. You can also put videos up on there.

Click to expand...

I might just wait until I've got over 30 posts, or whatever it is. Can't take too long I think. Thanks for the suggestion though.

mrmike said:

Anyway... we were talking about achromats. Using multiple lenses to focus a flashlight even further than any single lens can. The employee (I forgot his name but you may see him here sometime as "SurplusShedGuy") was telling me about something new they're going to have soon.

They're having black anodized, aluminum, machined tubes made for them (if I remember right it's about 4-6" long). The tube will come with universal adapters so you can attach the end to just about anything (camera/flashlight/whatever you want to use it for). It will also have retaining rings so you can put 3 lenses in it. So if you wanted to make your Malkoff Drop-in into a light saber... it should be easy to do.

I saw the test samples and they were nice (well, as nice as a threaded aluminum tube can be). They're supposed to be up for sale (on the website) very shortly.

Thought you guys would like to know. :candle:

Click to expand...

I'm not sure I understand how multiple lenses would work better than a single one with a long focal length. :thinking: Sounds very interesting though. I'd certainly like to turn my Fenix into a light saber...

How far away from the frontglas of the L2D did you place the lense?

ingokl said:

How far away from the frontglas of the L2D did you place the lense?

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Probably 14 to 17 mm when it's in focus, as the focal length of the lens is 35mm and It it looks like there's about 19mm to the led from the glass of the torch.

mrmike said:

...
Anyway... we were talking about achromats. Using multiple lenses to focus a flashlight even further than any single lens can. ...

They're having black anodized, aluminum, machined tubes made for them (if I remember right it's about 4-6" long)
...

Click to expand...

I was wondering if there is more information about how to use multiple lenses to focus an LED image. Do I want the focal point of the first to be at the emitter face? Do I want the same kind of lens for the second lens? Do I make that lens focus on the back of the first lens, the front of the first lens, the face of the LED, or the image of the LED through lens...

You mean doohickey?

daimleramg said:

You mean doohickey?

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Have you checked your doohicky lately? hehe


Anyone got a part number for that multilens thingamabob mentioned earlier from surplus shed. I cant find it.

Re: aspherical lensish kitchenated funnellized dadburned gimcrack

Jaz said:

I'm not sure I understand how multiple lenses would work better than a single one with a long focal length.

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I think you can continue to shape and refine the beam with additional elements... but with additional loss of light output compared to a single element - or no element at all. So what? Just kick it into turbo!

The quality of the glass will really start to matter with multiple elements.