Author Topic: Green Laser Pointer help  (Read 3266 times)

Andre Stubblefield

  • Active Astronomer
  • ***
  • Posts: 121
  • Activity:
    0%
  • Reputation: +0/-0
    • View Profile
Green Laser Pointer help
« on: December 24, 2017, 04:53:46 AM »
Hello! Although I have been doing this for a couple of years, today, I am still quite a beginner, particularly when it comes to this subject, so I am posting this here...
I am searching for advice and a recommendation for a laser pointer - can someone help?
I got a green pointer some time before, but it took odd, blue batteries, and they did not work more than, dun no, one or two times.  Do not work at all in the cold.  Paid $20 for this.  I then found it may have been more than 5 mW, which I have since found out is not good.  Got it on E-Bay, can't find the mfg./seller's info., so!  Starting from square one again.  I have done some research and this is what I have come up with that I Believe I need:
- green, 5 mW, course 3(a?)  Pointer  (seen some that say 3-5 mW, however I would like the five)
- something that you've used and works nicely, plus functions in the cold.  (New England kind of cold, which is!)
- requires lithium batteries (stated to work better in the cold)
- Would something which ordinarily takes alkaline batteries take lithium also?  I have seen a lot which do take regular ingestion.
- something created in the united states, or, if none, at least the distributor gives their contact info.  And they will work with the distributor on any difficulties.
- It would be nice if it had a switch on/off (versus push button), as a few times when using the one I'd, the push button would accidentally be pushed in my pocket or even within my hand.
- I think that's it!

Thanks so far!  Terry



kerolero

  • Active Astronomer
  • ***
  • Posts: 125
  • Activity:
    0%
  • Reputation: +0/-0
    • View Profile
Re: Green Laser Pointer help
« Reply #1 on: December 31, 2017, 04:05:51 PM »
Last year I bought a green 5mw laser off of Ebay for $4.49. I noticed their price is now $7.89.

I wanted to use it in place of a small finder, and asa pointer at star parties.

When I got it I found that it would fit into one of those small Tasco finders (with a little shimming):
Here it is mounted in a Tasco finder. It replaced the little original Unitron finder.
You can see it's button on the end.

I think it works very well. It does what I wanted it to do, and it sure beats the high prices I've seen elsewhere.

It comes with it's own batter recharger.




Brenton Crosby

  • Active Astronomer
  • ***
  • Posts: 112
  • Activity:
    0%
  • Reputation: +0/-0
    • View Profile
Re: Green Laser Pointer help
« Reply #2 on: January 03, 2018, 08:03:04 AM »
I use the ADM accessories laser and holder. VERY nice.

http://www.admaccess...er-accessories/

I have recharged the battery twice in 2 years, disclaimer - I don't use it a lot even though it is mounted on my scope.

I like that is has a key that you need to insert and turn on before the push button works.

presalacder

  • Active Astronomer
  • ***
  • Posts: 134
  • Activity:
    0%
  • Reputation: +0/-0
    • View Profile
Re: Green Laser Pointer help
« Reply #3 on: January 04, 2018, 05:12:50 PM »
Quote
I'm looking for information and a recommendation for a laser pointer - can someone help?
- green, 5 mW, class 3(a?) pointer  (seen some that say 3-5 mW, but I'd like the five)
- takes lithium batteries (said to work better in the cold)
- Something made in the USA, or, if none, at least the distributor gives their contact info. and they will work with the distributor on any issues.

Something certified to be 5mW (they actually hand them and hand-write a certification included with their GLPs), and sourced from the US is ZBolt.They also have a few models geared for astronomy (separate touch on-off button, battery models, etc)

I can't talk from experience, but when I was researching for green lasers, that brand came a lot with good reviews.

slotiniphin

  • Active Astronomer
  • ***
  • Posts: 116
  • Activity:
    0%
  • Reputation: +0/-0
    • View Profile
Re: Green Laser Pointer help
« Reply #4 on: January 07, 2018, 10:05:51 PM »
Thank you for all your replies! To the two who have used the green laser pointers, have you used them in the cold?
Ah, I knew there was another question - was wondering how the rechargable batteries do, and in the cold, too.

Chris Harwood

  • Active Astronomer
  • ***
  • Posts: 120
  • Activity:
    0%
  • Reputation: +0/-0
    • View Profile
Re: Green Laser Pointer help
« Reply #5 on: January 07, 2018, 10:17:37 PM »
There may be a use for those things if you are observing alone....but they are not generally too welcome at star parties. (At least after the general outreach star-tour.)

Alex

Roger Dixon

  • Active Astronomer
  • ***
  • Posts: 130
  • Activity:
    0%
  • Reputation: +0/-0
    • View Profile
Re: Green Laser Pointer help
« Reply #6 on: January 09, 2018, 12:45:17 AM »
I have seen them used many times in showing new people the night sky at outreach programs. I have used one my self to point out constellations and certain stars. It's never been an issue. I could see it could be an issue if someone was imaging, but that's not done at outreach.

Jeremy George

  • Active Astronomer
  • ***
  • Posts: 119
  • Activity:
    0%
  • Reputation: +0/-0
    • View Profile
Re: Green Laser Pointer help
« Reply #7 on: January 09, 2018, 07:41:26 AM »
The ADM one works fine any temperature I've had it in.

Michael Thompson

  • Active Astronomer
  • ***
  • Posts: 119
  • Activity:
    0%
  • Reputation: +0/-0
    • View Profile
Re: Green Laser Pointer help
« Reply #8 on: January 10, 2018, 04:10:31 AM »
I bought one at a scientific/surplus store.
It is effected by cold. I keep it in my inner coat pocket in the winter.

I just place it on the tube, and use the focuser flange of my reflector get it generally parallel with the optical axis.
I usually only use it to get my setting circles generally aligned.
I can quickly point the scope at a bright object with the laser and bam it's in my finder.

olaralal

  • Active Astronomer
  • ***
  • Posts: 131
  • Activity:
    0%
  • Reputation: +0/-0
    • View Profile
Re: Green Laser Pointer help
« Reply #9 on: January 10, 2018, 01:41:02 PM »
You get what you pay for, look at Orion laser finders with a mount for your scope.
The $20.00 ones are junk, a waist of $.

tersrhythopes

  • Active Astronomer
  • ***
  • Posts: 143
  • Activity:
    0%
  • Reputation: +0/-0
    • View Profile
Re: Green Laser Pointer help
« Reply #10 on: January 11, 2018, 01:17:17 AM »
Good thread. With the grandkid being 4 now and very interested in the night sky it's time I picked up a green/blue LP. Also find myself more in small outreach situations where a LP would be handy. The ZBolts with the on/off cable look pretty cool. The cable could be tied to the handle of some of the alt-az mounts like SV's M2 or TV's Telepod to give a quick targeting burst when panning. Makes me wonder why we haven't seen a built in LP and handle switch in some of the higher end alt-az mounts.

tricapenup

  • Active Astronomer
  • ***
  • Posts: 132
  • Activity:
    0%
  • Reputation: +0/-0
    • View Profile
Re: Green Laser Pointer help
« Reply #11 on: January 11, 2018, 03:49:30 AM »
All consumer grade lasers are affectedby cold because the laser LED crystalgeneration just stops at the certain point. Even though I'm in California, where it's rarely anywhere below 30 I do have that issue too but just because of the rechargeableAAA batteries failure. However, my friends from Siberia are reporting most certainfailure of the crystal near and under 0F after just a couple of minutes even with anexternal power source (car socket). An electric heating pad helps with that, though.

Keeping the pointer on your body unless really needed is the great immediate solution. All you need is some sort of a pointer base on the OTA, where you can clip the laser easily. Precise alignment with thumb set screws (which I saw at one of the links above) is the typical $50+ rip-off. You don't need that. On my Astroscan, I have just 2 simple ropes around the OTA and can tuck my pointer ends under both, move it to lay flat against the focuser bump in order to align with the OTA, and finally rotate to push the button against that bump in just a couple of seconds. I then can see the tip of the laser beam exactly at the center of the 40x FOV of the scope.
That's a lucky coincidence indeed, but note - no any screws necessary, just a prealigned base with simplistic clipping. If not yet convinced, consider this: even though, I have a decent 3D printer at home and can print anything imaginable just overnight, including the entire Astroscan OTA replica with the laser holder integrated - I don't even bother improving that rope mount, as it's simply perfect.


Artavius Murphy

  • Active Astronomer
  • ***
  • Posts: 113
  • Activity:
    0%
  • Reputation: +0/-0
    • View Profile
Re: Green Laser Pointer help
« Reply #12 on: January 11, 2018, 12:54:26 PM »
I don't want to say too much here but the cheap ones may have a safety concern,
as they may be missing a vital IR block filter,
as the cheap tech has to do with halving the wavelength to produce the green,
but does have substantial invisible laser energy leaking as well,
-energy that one cannot see, eyeballs do not have a (close eyes because it is bright reflex),
and can possibly have more mw energy behind it than the rating at the green wavelength.....
Even though the bright green causes your pupils to dilate, reflections of the beam and looking at it in the dark (pupils wide open),
one cannot possibly tell that there is bright invisible energy that can be entering your eye and can las your retina.
And retina damage is not painful and not immediately detectable sometimes.......
FWIW.
http://www.nbcnews.c...laser-pointers/

Cory Bass

  • Active Astronomer
  • ***
  • Posts: 148
  • Activity:
    0%
  • Reputation: +0/-0
    • View Profile
Re: Green Laser Pointer help
« Reply #13 on: January 11, 2018, 03:56:29 PM »
As a pilot, although not currently flying, I would like to share just how dangerous green lasers are.
http://mentalfloss.c...ointer-aircraft
Even if you're not intentionally aiming at an airplane, if you're anywhere within 30 miles or so of a large airport, you can have not only commercial, but civilian, law enforcement, or military aircraft overhead. Even those 5mW lasers, as seen in this story, can be pretty damaging inside the cockpit.
I don't recommend shining ANY laser up into the air, either as a pointer or other style of device for tracking or aligning to start.
Don't use a laser!

More references.
http://abcnews.go.co...ory?id=32499432
http://www.laserpoin...s_aircraft.html
http://www.bbc.com/news/uk-35576741

Cory Bass

  • Active Astronomer
  • ***
  • Posts: 148
  • Activity:
    0%
  • Reputation: +0/-0
    • View Profile
Re: Green Laser Pointer help
« Reply #14 on: January 12, 2018, 01:17:14 AM »
I have this one. Don't believe the sales hype, it's still a 5mW, and won't burn anything. That said, it has a brilliant, big beam than never fails to elicit an "Ooh" from people when they see it, astronomers included.

<p class="citation">Quote
if you're anywhere within 30 miles or so of a large airport, you can have not only commercial, but civilian, law enforcement, or military aircraft overhead. Even those 5mW lasers, as seen in this story, can be pretty damaging inside the cockpit.
[/quote]

Quite true. As a pilot, I call KSAV's tower, give them my tail number, tell them we'll be out and using lasers, and that I'll have my handheld with me. If any traffic is getting near, they can call my via my tail number, and I'll make the announcement to kill all the laser light till they call me back and issue a "traffic no factor."

.Joe