Do You Guys Use Green Laser Pointers?

On Sat, 17 Sep 2005 09:40:56 -0700, "Mij Adyaw"
wrote:

Do you guys still use green laser pointers? I have been paranoid ever since
some idiot got arrested several years ago for pointing a laser pointer at a
plane.Someone may call the police and make false accusations. It is
unfortunate because green laser pointers are a great teaching tool and also
work well as a finder. Do you guys think that I am overly paranoid?

-mij


I never stopped using mine.


-JATO
http://jatobservatory.org

Good question. I have wondered about that myself.
Remember, the guy who got into trouble was next to an airport and
he apparently didn't just "mistakenly" hit a plane he was hitting it!

I think you would be fine if when you use it you are most careful. If
you see a plane, turn it off and only use it for a few minutes at a
time.

Of course be careful of where you point the thing. I think most of us
would be most careful but there are those who seem to check their
common sense at the door..

Best,

Ed

They can be dangerous if not handled properly. If you point such a green
laser into somebody's eye, there is a good chance that it can be
damaged. If you do that with a 5mW green laser, it's almost certain.


--
observer

Bernhard Rems
Editor - 'The Astronomers' (http://theastronomers.com)

On Wed, 21 Sep 2005 02:59:42 -0500, observer
wrote:

They can be dangerous if not handled properly. If you point such a green
laser into somebody's eye, there is a good chance that it can be
damaged. If you do that with a 5mW green laser, it's almost certain.

No, a 5mW green laser is not dangerous. It can't cause any permanent
damage to the eye- at worst, it is an annoyance. At that energy level,
it takes several seconds to produce any damage (and more than 15 seconds
for thermal damage). Such an exposure is not possible by accident. And
beyond a few meters, 1/r^2 power loss means there is no way to get the
full laser output into the eye in any case.

The aesthetics of a lot of pointers at a dark star party location is
really about the only rational argument against them- not safety.

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

"Chris L Peterson" wrote in message
...

The aesthetics of a lot of pointers at a dark star party location is
really about the only rational argument against them- not safety.

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

Oh, I dunno about that, Chris.
If a GLP spot hits the barrel of my (white) scope when I'm dark adapted, and
I see it, I'm blind for half an hour.
Those spots are damnably bright!

Maintaining dark adaption is hardly "just aesthetics" when observing - yes?

--
Jeff R.

Chris L Peterson wrote:

No, a 5mW green laser is not dangerous. It can't cause any permanent
damage to the eye

For all practical purposes, that's true.

at worst, it is an annoyance ... aesthetics [is] the only rational
argument against them

That's stretching the commonsense meaning of "annoyance."

Automobile headlights also can't cause permanent damage to the eye.
But if somebody turned on their headlights at a star party when
their car was pointed at you, it would be worse than an annoyance.
For an astrophotographer, it could ruin a night's work. For a
visual observer, it could mean a half hour lost while recovering
dark adaptation.

Likewise, irresponsible use of a laser pointer can be worse than
an annoyance. Exactly what's responsible and irresponsible is
debatable, of course. I think everyone would agree that pointing
one at someone or something on the observing field would be
irresponsible. At the opposite extreme, if the star party were
explicitly to educate the general public, and somebody was
designated to point out constellations to a group of newbies,
I don't think that anybody would object to the use of a laser
pointer.

- Tony Flanders

On 21 Sep 2005 08:19:54 -0700, wrote:

That's stretching the commonsense meaning of "annoyance."

I don't think so. By "annoyance" I only mean that there is no physical
harm. But certainly, for someone who has spent a couple of hours
becoming very well dark adapted, the annoyance is a severe one.


Likewise, irresponsible use of a laser pointer can be worse than
an annoyance...

Of course, if someone is engaged in an activity where a sudden loss of
vision is dangerous- driving is the most obvious example- then
"annoyance" is too mild a word. But you've struck upon the important
issue: responsibility. If you trust your star party attendees to be
responsible in other ways, such as managing headlights and flashlights,
then there is little reason to ban GLPs. If you don't trust them- well,
that's the sort of star party I'll pass up, thank you.

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

On Thu, 22 Sep 2005 01:17:27 +1000, "Jeff R" wrote:


Oh, I dunno about that, Chris.
If a GLP spot hits the barrel of my (white) scope when I'm dark adapted, and
I see it, I'm blind for half an hour.
Those spots are damnably bright!

Maintaining dark adaption is hardly "just aesthetics" when observing - yes?

I was only addressing the issue of safety. There is simply no excuse for
a laser to hit your scope- anyone who abuses a GLP that way should be
summarily sent home. Banning GLPs at star parties because you don't have
responsible attendees is attacking the wrong problem, IMO.

By "aesthetics" I was referring to the appearance of lasers in the sky.
The beams have no impact on visual observers or imagers, and if you are
in a good site they will be nearly invisible. But many star parties are
not held at very good sites, and the appearance of green lines in the
sky may detract from the overall experience for some people. That is a
valid reason to place some limitations on GLP usage.

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

Sorry to disappoint, but they "can"...note the operative word here
"CAN" be dangerous...just like anything else. Wavelength and length of
exposure (and of course, the wattage rating) are the key to whether
they can cause any discomfort, temporary, or permanent damage.

Dr. Robert Young

Check out

http://www.sciam.com/askexpert_quest...B7809EC588F2D7

on potential eye damage from laser pointers. The "green" ones are
mentioned explicitely interesting enough. Covers some areas that are
not at all "obvious" on first thought.