Green Laser Pointer

[crosscountry]

anyone else have one? Radio Shack has them on sale right now for $40, and I got myself a little present.

It is SO COOL. Right now it's cloudy and drizzly, but I could see the laser beam all the way to the sky. It's amazing.


Besides astronomy stuff what other uses have you all found?

[Torsten]

I have a 40 mW green laser. I bought it to put a reference point into scenes I was photographing such that it would be a known distance from the centre of the images, thereby providing a convenient scale. It was some goofy concept I was playing with when I had too much time on my hands.

[mugaliens]

Interesting, Torsten - I used to use a red laser pointer to help focus night scenery shots with my old SLR Canon (extended exposures, of course). I had a difficult time getting an accurate focus with medium-range shots, even with the built-in IR focus mechanism.

[sarongsong]

...what other uses have you all found?

Well, there's always the nuclear gummy explosion and green pumpkins...and lighting up a clear beaker of colloidal silver in a darkened room...

[djellison]

They are cool - but I'd advise against buying cheap ones off ebay. I've had two, and the button has broken on both. First time it got broken at Europlanet by a French scientist ( archives of planetary.org/blog for details ) . The replacement has had a dodgy button since day 1.

Spending a few more $ on one would make sense to get a good one I think

Doug

[crosscountry]

well, mine feels nice, but I'll take good care of it anyway.


I'll try to think of a way to incorporate it into my photography. Sky spelling might be the way to go. Thanks for the idea.

[Mister Earl]

I've seen green lasers that can cut electrical tape and burn skin. The amount of shenanigans you can employ with such a device is not measurable. Want!
I always wanted to get one of those and hook it up to a bank of disposable-camera accumulators-and-capacitors (Note the use of "I do not know the correct terminology" words, hehe) and see if you can make a neat little pulse laser out of it.

[publiusr]

I think someone is working on a one watt laser.

Oldie
http://ao.osa.org/ViewMedia.cfm?id=14288&seq=0

[tofu]

I got mine from thinkgeek.com. I haven't had any trouble with it. Aside from pointing out stars, it has all the normal uses; presentations, triggering the hunting instinct of cats, etc.

[Frog march]

I used to have red laser, but the button went.


If you point them at road signs, the whole sign lights up.

you can also burn some toast and have a laser show.


or, more pleasantly, boil a kettle for a few minutes.

[publiusr]

http://www.spacewar.com/reports/Boei...craft_999.html

Instead of Puff the Magic Dragon--I guess we call it Zak...from the C-130 Herculoids

[Dragon Star]

I want one of those Hercules-400 Lasers, capable of a peak 500mW.

Only a little less then $3,000.

[crosscountry]

I had some fun the other night with it. Snapped these on a short timed exposure.

[tdvance]

I was going to say "what's the brick wall pattern, something to do with interference?"

but then I looked at the second picture and...it's a brick wall!

[Neverfly]

I was going to say "what's the brick wall pattern, something to do with interference?"

but then I looked at the second picture and...it's a brick wall!

It's a good idea to be able to recognize them. The idea gets even better exponentially as velocity increases.

[crosscountry]

haha. I tried some new ones, will have to post them soon.

[tofu]

Something odd that I could probably start a new thread over, but I'll post it here anyway. I'm nearsighted and have astigmatism. Without my glasses on, I see the spot made by the laser as several distinct points. I see this regardless of the surface the laser is shining on. I can't see it with a red laser, but that's probably because I don't have a red laser that's bright enough.

What's odd, to me, is that I don't see the standard out of focus image. Why am I seeing separate distinct spots?

[Neverfly]

Something odd that I could probably start a new thread over, but I'll post it here anyway. I'm nearsighted and have astigmatism. Without my glasses on, I see the spot made by the laser as several distinct points. I see this regardless of the surface the laser is shining on. I can't see it with a red laser, but that's probably because I don't have a red laser that's bright enough.

What's odd, to me, is that I don't see the standard out of focus image. Why am I seeing separate distinct spots?

The first image- is what a human sees.
The second is what a housefly sees.
The last is what a bird sees (usually on shoulders and bald heads) (OOhh! and freshly washed cars too!).

Conclusion: You are a housesfly. Quit this nonsense- find a garbage can and a mate.

[Mister Earl]

Something odd that I could probably start a new thread over, but I'll post it here anyway. I'm nearsighted and have astigmatism. Without my glasses on, I see the spot made by the laser as several distinct points. I see this regardless of the surface the laser is shining on. I can't see it with a red laser, but that's probably because I don't have a red laser that's bright enough.

What's odd, to me, is that I don't see the standard out of focus image. Why am I seeing separate distinct spots?

I am also nearsighted, also with the Astymatism, and I see a similarity myself. When closely looking at the laser dot, the light itself appears to have some granularity.

[BigDon]

I use a laser to point out interesting things in tidepools. Works better than, "Over there, next to the bryozoans" especially with kids.

[stavroj]

Yes, they are cool. I think that red produces a finer point though.

[tdvance]

looks like the result of a "hartman disk"--a focusing aid that is a disk with several holes in it that one puts over a telescope or camera lens. If it is in focus, you see one image. If not, you see a separate image for each hole. So, perhaps the laser aperture actually has 7 holes in it in that pattern?

[crosscountry]

Yes, they are cool. I think that red produces a finer point though.

I guess you're right. I mean at 20 meters that red one only looks enormous compared to my green one at 2000 meters.

[mickal555]

I've had a green 55mW for a few years. Pretty fun. It was $100 bucks from wicked lasers.

[tofu]

If you've got a kilobuck laying around, you can be the first kid on your block to own a blue laser pointer.

[Blondin]

I have a mounting attachment for my green laser that fits my telrad base so I can use the laser as pointing device on my scope. It's a lot easier than cranking your neck to look through the telrad (especially when you're trying to locate something near the zenith). The only problem is that performance is greatly degraded in really cold weather so it's not the best thing for northern Ontario winters.

[beamq]

If you just want to use it as skypointer, the pointer with 5mw power is enough. Don't get high power lasers. They're dangerous.

[One Skunk Todd]

I recently got a green laser and I have discovered that if I shine it at objects of a certain color the dot turns yellow. Anything that's a salmony/peachy/pink color will make it happen, including pink post-it notes, and certain pink nail polishes.

What was even weirder was shining it on a clear plastic "exit" sign which had lighted, red/fuschia letters. The spot on the letters was yellow but the reflected dot on the ceiling was green. After a while I realized the green spot must be partially reflecting off the clear plastic casing while the yellow spot was light actually coming back from the letters themselves. Still not sure why it changed to yellow though.

Another trick I was shown (not sure if it's real) is to reflect the laser off of a CD or DVD and you can see the lands and pit of the surface.

I have a Beamshot GB100 <5mw and like others am having trouble with the switch.

[crosscountry]

no trouble with my switch, but I don't play with mine as much anymore. of course it's there when I need it.


So far the girls to whom I show the stars like it a lot too.

[tdvance]

I recently got a green laser and I have discovered that if I shine it at objects of a certain color the dot turns yellow. Anything that's a salmony/peachy/pink color will make it happen, including pink post-it notes, and certain pink nail polishes.

What was even weirder was shining it on a clear plastic "exit" sign which had lighted, red/fuschia letters. The spot on the letters was yellow but the reflected dot on the ceiling was green. After a while I realized the green spot must be partially reflecting off the clear plastic casing while the yellow spot was light actually coming back from the letters themselves. Still not sure why it changed to yellow though.

Another trick I was shown (not sure if it's real) is to reflect the laser off of a CD or DVD and you can see the lands and pit of the surface.

I have a Beamshot GB100 <5mw and like others am having trouble with the switch.

Shining a green light on a red light and seeing yellow is no surprise--true yellow light stimulates green and red cones in the eye about equally, so green and red light of comparable brightness entering the eye will appear yellow. The green light is not turned yellow so that's why its reflection on the ceiling is still green.

As for the pink post-it notes--well, that could be a contrast effect--just as light gray looks almost white against black but looks gray against white.