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gonna try a 375nm pointer build...

diachi

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I can't see it either. There's been something weird going on with the LPF-hosted images lately.
No joke. I can testify that there is an image posted. :thinking:
The image is of a nice HeCd pointing at a piece of paper and creating a lovely blue bright dot.

It might be my profile privacy, albums are set to "friends only".

I've changed it to "registered members", let me know if it's working now.

Edit: That worked apparently. Please check the original post now! :beer:


No...really thought it was a joke because 325nm isn't visible
Haha, nope, no joke! :)
 
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Rivem

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It might be my profile privacy, albums are set to "friends only".

I've changed it to "registered members", let me know if it's working now.

Here's an Imgur re-host just in case.
Yep. See the original now.
 

GSS

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Ok, see it now:)
Yup looks on the blue side..
 
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diachi

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Ok, see it now:)
Yup looks on the blue side..

That's just the fluorescence, the beam itself is invisible, it just fluoresces everything. Well not everything, but most stuff you'll find in your house.
 

paul1598419

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Hey, styropyro. Looking forward to seeing what you come up with once you extract the diode. You're right, Don't see many 375nm pointers around.
 

Cyparagon

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375nm is certainly not invisible, although it's almost as dim as NIR. I'd describe it as a dull grey.
 

diachi

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375nm is certainly not invisible, although it's almost as dim as NIR. I'd describe it as a dull grey.
That's what 325 looks like to me, I figured there was still some very weak fluorescence action or something else going on which was causing that very dim grey-ish glow.
 

CDBEAM777

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That's a really good idea! I tried this nearly a decade ago by squeezing highlighters into my fog machine fluid and it had no noticable effect. But I'm a chemist now dammit and I can come up with something much stronger. I have a lot of fluorescein and analogs around and can try using that for an air glow. it's not phosphorescent so it won't leave glow trails (well it will for roughly 10 billionths of a second) but it still might make a cool effect. Hopefully propylene glycol will act as an adequate solvent and not quench the fluorescence.

I will also look into this astral driver.


Don't forget what forum you're on :D and I'm sad I didn't get more microboost drives too.
Hmmmm...I am having a " Vision ( Happens a lot hahaha )....Styro...Messing with Flourescent Goo....to make UV responsive FOG....all done to the tune...
" Monster Mash "...WOW !!! Gary Garcia would luv it !!!

Hmmm...and replace the beams with light cones....that would just appear....from thin air ....and...drift off.....into the Either !!!! morphing and shape shifting as they drift away on the air currents !!!

Hey.... " It Could Work " :san::san::san:

...." He did the Mash....the Monster Mash "

Later...CDBEAM
 

styropyro

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375nm is certainly not invisible, although it's almost as dim as NIR. I'd describe it as a dull grey.
This is exactly how I remember 355nm. I just assumed what I saw was fluorescence. I can't remember if it looked out of focus at all. Perhaps the cornea fluoresces in UVA?
 

Encap

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Here is what one researcher reports about visual perception of ultraviolet light and lower:

"Over the years they've done plenty of vision studies involving ultraviolet, both on normal people and aphakics (people missing a lens in at least one eye). The color varies depending on the intensity. At high intensity it tends to look white or grey, at low intensity like grayish violet. At middle intensities it looks violet down to 395 nm (±5). Below that it trends toward bluish gray, becoming pure gray at 375 nm. Below that it trends towards blue, becoming pure blue at 350 nm. Below that it trends back towards gray.

Down to about 334 nm, the colors are about the same for normals and aphakics. Below that, color fades out faster for normals.

The lowest wavelength at which people still have some visual acuity and color perception is 310 nm. At that wavelength, people can still read an eye chart, but only at a distance of 4 inches. (Normally people can't even focus that close, but at 310 nm they can.)"

Between 310 and 302 nm the opacity of both the lens and cornea increase by several orders of magnitude. At 302 nm people only see a gray blur, and only with 1-hour dark-adapted eyes and if the uv is intense. At 310 nm, on the other hand, eyes don't need to be dark-adapted, the room lights can be kept on.

Starting around age 30-45 the lower limit of vision in the ultraviolet starts to go up, so that the middle-aged can usually see uv only down to about 334-365nm."

"The lens of the eye absorbs ultraviolet light (which is fortunate since UV has a different focal length than white light) .
This means that all the other colors can be focused into a sharp image. but adding UV acts to blur it."
 
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Alaskan

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Interesting, the last sentence sure shows how well nature has designed our eyes, even the material of the eyes lens help vision by attenuating UV.
 

paul1598419

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I seriously doubt the cornea fluoresces, or if it does it isn't seen as a beam. It would have to be out of focus as the cornea is too close to the lens to be in focus.
 

styropyro

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Here is what one researcher reports about visual perception of 375nm and lower:

"Over the years they've done plenty of vision studies involving ultraviolet, both on normal people and aphakics (people missing a lens in at least one eye). The color varies depending on the intensity. At high intensity it tends to look white or grey, at low intensity like grayish violet. At middle intensities it looks violet down to 395 nm (±5). Below that it trends toward bluish gray, becoming pure gray at 375 nm. Below that it trends towards blue, becoming pure blue at 350 nm. Below that it trends back towards gray.

Down to about 334 nm, the colors are about the same for normals and aphakics. Below that, color fades out faster for normals.

The lowest wavelength at which people still have some visual acuity and color perception is 310 nm. At that wavelength, people can still read an eye chart, but only at a distance of 4 inches. (Normally people can't even focus that close, but at 310 nm they can.)"

Between 310 and 302 nm the opacity of both the lens and cornea increase by several orders of magnitude. At 302 nm people only see a gray blur, and only with 1-hour dark-adapted eyes and if the uv is intense. At 310 nm, on the other hand, eyes don't need to be dark-adapted, the room lights can be kept on.

Starting around age 30-45 the lower limit of vision in the ultraviolet starts to go up, so that the middle-aged can usually see uv only down to about 334-365nm."

"The lens of the eye absorbs ultraviolet light (which is fortunate since UV has a different focal length than white light) .
This means that all the other colors can be focused into a sharp image. but adding UV acts to blur it."
Thanks for finding that info! So I guess I was actually seeing 355nm. Crazy that humans can see nearly 100nm below what is considered the visible spectrum. More impressive being on the blue side of the spectrum, where the photon energy at 300nm is 1/3 higher than at 400nm. For NIR (800nm compared to 700nm) the energy is only 1/7 higher.
 




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