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Long distance 1.4 Watt 520nm beamshots

Alex2893

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diachi

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Cool! That "dot" is huge at 2.6 miles!

Should have had someone go to the other end of the beam to capture some nice long distance beam shots - that'd have looked damn cool. Light scatters more in that direction so the beam would be brighter at the other end facing back towards the laser.
 

Alex2893

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just by guessing id say the bar is 100 feet long at that distance.
 

CurtisOliver

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Those shots were good. :) It is nice to see the clear distinction between the slow and fast axis. Are you going to do this again with beam correction? We should try this with a NUBM44. :D The dot may bathe a collection of trees in blue light.
 

diachi

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Those shots were good. :) It is nice to see the clear distinction between the slow and fast axis. Are you going to do this again with beam correction? We should try this with a NUBM44. :D The dot may bathe a collection of trees in blue light.

Wonder if you could light a match at that distance with a NUBM44 and a big enough Fresnel lens? :crackup:
 

Alex2893

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When I can afford one I want a 6,7 watt 445nm and a beam expander maybe a sanwu. and a beam expander for my 1.4 watt 520.

I dont go here that often. usually just for july 4th
 

CurtisOliver

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When I can afford one I want a 6,7 watt 445nm and a beam expander maybe a sanwu. and a beam expander for my 1.4 watt 520.

I dont go here that often. usually just for july 4th
It would be good to have a beam expander. But i know, this hobby can hit finances hard.

Wonder if you could light a match at that distance with a NUBM44 and a big enough Fresnel lens? :crackup:
:thinking: I wonder. :D I would love to try. Just get one of those rear projection tv lens. Should be able to get enough of the beam for it to light a match.
 
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CurtisOliver

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:kewlpics: They are nice flashlights, but I prefer the laser :D
 

trencheel303

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that's epic, it's amazing how much power you get of a mere Watt that at over a mile, and spread out to a bar, its still visible as light in broad daylight.

Nice torches/flashlight as well.
 

Dr_Evil

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Nice shots. That's some horrible divergence though. I need to come up with a design that makes the beam more round or square and maybe runs off of one or 2 26650s. It would be nice to have something bright
 

Cel

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Nice pics! :beer:

Regarding the first post, which lens are you using?
 

diachi

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:can: This have 2 stripes, though other pictures have only one. :confused:
My guess would be the beam moved while the camera's shutter was still open. At those kind of distances a little bit of movement at the source creates a large rapid movement where the beam terminates.
 
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Eracoy

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I am curious about the maths involved in dot size and energy reaching the terminal beam point if a beam expander is involved. The expander I have is a LaserGlow X10DR 10x expander that I have adapted to be a universal fit. It has two adjustment points by twisting either the expander's lens or the expander base. So, the effect is that I can adjust both the beam's focus AND the expansion factor. Also, because I have such a long lens holder, it can go well beyond 10x expansion factor. I'd say easily 20x. The problem is, then, that the beam is clipped on the outside, because the exit aperture has a finite diameter. Does anyone have any ideas about how to calculate the way to get the most beam intensity (W/m^2) at the final (large) dot? I think it is possible to define the optimal beam expansion factor in terms of only the distance the beam will travel. Might this be something to ask in more detail in the Optics section?
 




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