Go Back   IceInSpace > Beginners Start Here > Beginners Equipment Discussions

Reply
 
Thread Tools Rating: Thread Rating: 3 votes, 2.33 average.
  #1  
Old 04-04-2017, 09:09 PM
ninja2's Avatar
ninja2 (Chris)
Chris

ninja2 is offline
 
Join Date: Jan 2015
Location: Adelaide North East
Posts: 45
What laser pointer is best ?

Hello again IIS...

I was watching "Stargazing Live" on ABC tonight and reminded of the value of a good laser pointer in astronomy.

I'm in process of rejoining ASSA and so I'm aware of the laws about lasers > 1mW and safety guidelines, but I need some guidance about what brands, power and features are best, and typical cost. As an example ... how powerful was that laser brandished in the "Stargazing Live" show? It ws impressive, but maybe it's more than I need?

thanks in advance
Reply With Quote
  #2  
Old 05-04-2017, 05:29 AM
gaseous's Avatar
gaseous (Patrick)
Registered User

gaseous is offline
 
Join Date: May 2016
Location: Brisbane
Posts: 782
Hi Chris, I bought a generic green laser off eBay last year for about $20. Listed as <1kw, the delivered product had <5kw on the sticker so it may be more powerful than strictly allowed, depending on where you live. It's a great device. Mine has a removable rechargeable battery that I had to buy separately from Battery World for another $20 or so, but for $40 it does the trick, similar to that shown in the show last night.
Reply With Quote
  #3  
Old 05-04-2017, 05:40 AM
sil's Avatar
sil (Steve)
Not even a speck of dust

sil is offline
 
Join Date: Jun 2012
Location: Canberra
Posts: 1,474
no difference between brands etc. no features beyond on or off. Green laser is all you need to look for. The one Greg was using on the show you are ignoring the fact it was humid there so LOTS of moisture in the air for the photons to bounce off (light itself IS invisible after all) plus as they demonstrated you were watching them through a low light camera that amplified the effect, its not that bright in person. Plus of course they are not toys and of course can be see miles away so if you're in a suburban area the police can see where the laser line is pointed from.
Reply With Quote
  #4  
Old 05-04-2017, 06:05 AM
Malcolm
Registered User

Malcolm is offline
 
Join Date: May 2015
Location: Lismore NSW Australia
Posts: 242
Not too many of these work well in cold weather. Mine is scope mounted and the solution was to wrap it in a USB powered heater pad run by a phone battery charger. I think I paid around $6 on eBay.
Reply With Quote
  #5  
Old 05-04-2017, 07:01 AM
DavidTrap's Avatar
DavidTrap (David)
Really just a beginner

DavidTrap is offline
 
Join Date: Jun 2009
Location: Brisbane
Posts: 3,032
I just looked into a 20mW version from a "reputable" supplier vs eBay - roughly $300 shipped.

My 1mW ebay one is rather dim and unusable in the city, but definitely visible under dark skies.

I agree that the one being used on Stargazing Live was either a high powered one or definitely amplified by the fancy camera they were using - maybe a bit of both.

DT
Reply With Quote
  #6  
Old 05-04-2017, 07:16 AM
ninja2's Avatar
ninja2 (Chris)
Chris

ninja2 is offline
 
Join Date: Jan 2015
Location: Adelaide North East
Posts: 45
Thanks all ... pretty straight forward then.

Although @gaseous .... 5kW for $20? hmmmm, great price but not sure I need that much oomph!
Reply With Quote
  #7  
Old 05-04-2017, 07:55 AM
sil's Avatar
sil (Steve)
Not even a speck of dust

sil is offline
 
Join Date: Jun 2012
Location: Canberra
Posts: 1,474
Quote:
Originally Posted by Malcolm View Post
Not too many of these work well in cold weather. Mine is scope mounted and the solution was to wrap it in a USB powered heater pad run by a phone battery charger. I think I paid around $6 on eBay.
Nothing to do with "one of those". Batteries dont work well in cold temperature.
Reply With Quote
  #8  
Old 05-04-2017, 08:16 AM
issdaol (Phil)
Registered User

issdaol is offline
 
Join Date: Dec 2009
Location: Canberra
Posts: 688
Quote:
Originally Posted by DavidTrap View Post
I just looked into a 20mW version from a "reputable" supplier vs eBay - roughly $300 shipped.

My 1mW ebay one is rather dim and unusable in the city, but definitely visible under dark skies.

I agree that the one being used on Stargazing Live was either a high powered one or definitely amplified by the fancy camera they were using - maybe a bit of both.

DT
$300 is quite expensive for a 20mW laser pointer !

A deeper look around should give some better priced options from other reputable suppliers.
Reply With Quote
  #9  
Old 05-04-2017, 08:26 AM
glend (Glen)
Registered User

glend is offline
 
Join Date: Jun 2013
Location: Lake Macquarie
Posts: 7,033
All laser pointer are bad, especially for imagers. If you have ever had some well meaning idiot 'accidently' wave a laser past the front of your scope while your observing you will know why they are dangerous. It was bad to see a so-called expert using a laser pointer during the ABC Stargazing Live show last night, when someone was observing right through the light path.
They can only be justified as a knowledge sharing device, when at a dark site and no one is at a scope or imaging.
And of course, in any sort of urban environment they will have the police knocking at your door.
Reply With Quote
  #10  
Old 05-04-2017, 08:38 AM
gaseous's Avatar
gaseous (Patrick)
Registered User

gaseous is offline
 
Join Date: May 2016
Location: Brisbane
Posts: 782
Quote:
Originally Posted by ninja2 View Post
Thanks all ... pretty straight forward then.

Although @gaseous .... 5kW for $20? hmmmm, great price but not sure I need that much oomph!
This is the bad boy here. Listed as <1kw but maybe they need the sticker to say <5kw in case it's actually 1.1kw or something. They come with an end piece that produces a sparkly multi-dotted effect, so you need to unscrew this end piece to get the single beam, which is maybe how they get away with selling it as more than 1kw. I wouldn't say it's a lot of oomph, but it certainly does the job, and as others have said, you won't make many friends at a star party if you start waving it in front of people trying to image/observe.

http://www.ebay.com.au/itm/Green-Las...item5b25b192cc
Reply With Quote
  #11  
Old 05-04-2017, 08:46 AM
ninja2's Avatar
ninja2 (Chris)
Chris

ninja2 is offline
 
Join Date: Jan 2015
Location: Adelaide North East
Posts: 45
@gaseous, that "looks" like a suitable device
now I'm sure you meant mW not kW ... a factor of 1,000,000 difference there !
Reply With Quote
  #12  
Old 05-04-2017, 08:49 AM
issdaol (Phil)
Registered User

issdaol is offline
 
Join Date: Dec 2009
Location: Canberra
Posts: 688
Quote:
Originally Posted by glend View Post
All laser pointer are bad, especially for imagers. If you have ever had some well meaning idiot 'accidently' wave a laser past the front of your scope while your observing you will know why they are dangerous. It was bad to see a so-called expert using a laser pointer during the ABC Stargazing Live show last night, when someone was observing right through the light path.
They can only be justified as a knowledge sharing device, when at a dark site and no one is at a scope or imaging.
And of course, in any sort of urban environment they will have the police knocking at your door.
Thats a bit like saying All 4WD's are bad because a few people don't pay attention or know how to drive/handle a 4WD compared to a small sedan

Pointers have a purpose and in the hands of a responsible person paying proper attention they are perfectly fine
Reply With Quote
  #13  
Old 05-04-2017, 08:51 AM
gaseous's Avatar
gaseous (Patrick)
Registered User

gaseous is offline
 
Join Date: May 2016
Location: Brisbane
Posts: 782
Quote:
Originally Posted by ninja2 View Post
@gaseous, that "looks" like a suitable device
now I'm sure you meant mW not kW ... a factor of 1,000,000 difference there !

Yep, my bad!
Reply With Quote
  #14  
Old 05-04-2017, 08:52 AM
ninja2's Avatar
ninja2 (Chris)
Chris

ninja2 is offline
 
Join Date: Jan 2015
Location: Adelaide North East
Posts: 45
Quote:
Originally Posted by glend View Post
And of course, in any sort of urban environment they will have the police knocking at your door.
Is a 1mW laser simply not powerful enuf to be visible from a distance and so doesn't attract police attention, but a 5mW is easily visible from a distance? Or is this only true if the conditions are right (e.g. humidity).

(only curious ... not planning to test police response unit)
Reply With Quote
  #15  
Old 05-04-2017, 08:54 AM
LewisM's Avatar
LewisM
Novichok test rabbit

LewisM is offline
 
Join Date: Aug 2012
Location: Somewhere in the cosmos...
Posts: 10,388
The guy observing in the background was merely a "prop" - he was not really observing per se. I suppose they should have turned the lighting off too so he could "observe".

Lasers, guns, cars, knifes, sticks...ban 'em all cause they are dangerous
Reply With Quote
  #16  
Old 05-04-2017, 09:36 AM
doppler's Avatar
doppler (Rick)
Registered User

doppler is offline
 
Join Date: Nov 2012
Location: Mackay
Posts: 1,656
Quote:
Originally Posted by ninja2 View Post
Is a 1mW laser simply not powerful enuf to be visible from a distance and so doesn't attract police attention, but a 5mW is easily visible from a distance? Or is this only true if the conditions are right (e.g. humidity).

(only curious ... not planning to test police response unit)
Side on, a laser beam is only visible for maybe 50 meters because the beam is only a couple of mm wide (we've done a few school viewing nights across the road from the police station without being noticed), however the beam can travel for many kilometers so is very visible at a distance if pointed directly at you.
Reply With Quote
  #17  
Old 05-04-2017, 09:45 AM
doppler's Avatar
doppler (Rick)
Registered User

doppler is offline
 
Join Date: Nov 2012
Location: Mackay
Posts: 1,656
Quote:
Originally Posted by gaseous View Post
Hi Chris, I bought a generic green laser off eBay last year for about $20. Listed as <1kw, the delivered product had <5kw on the sticker so it may be more powerful than strictly allowed, depending on where you live. It's a great device. Mine has a removable rechargeable battery that I had to buy separately from Battery World for another $20 or so, but for $40 it does the trick, similar to that shown in the show last night.
You can get those rechargeable batteries on ebay from Australian warehouses for a couple of $ each. The good thing about buying lasers from Australian ebay suppilers is that they have already passed though customs.
Reply With Quote
  #18  
Old 05-04-2017, 10:05 AM
dannat's Avatar
dannat (Daniel)
daniel

dannat is offline
 
Join Date: Sep 2007
Location: Macedon shire, Australia
Posts: 3,426
Quote:
Originally Posted by LewisM View Post
The guy observing in the background was merely a "prop" - he was not really observing per se. I suppose they should have turned the lighting off too so he could "observe".
they were using some kind of IR camera -they did a demo with a normal camera & it was nearly pitch black
Reply With Quote
  #19  
Old 05-04-2017, 01:39 PM
LewisM's Avatar
LewisM
Novichok test rabbit

LewisM is offline
 
Join Date: Aug 2012
Location: Somewhere in the cosmos...
Posts: 10,388
Without watching it again, they did say turning off the lights before they showed how dark it was, so i don't any i.r used at all. IR is usually b&w.
Reply With Quote
  #20  
Old 05-04-2017, 10:40 PM
Stardrifter_WA
Life is looking up!

Stardrifter_WA is offline
 
Join Date: Sep 2010
Posts: 2,017
Quote:
Originally Posted by Malcolm View Post
Not too many of these work well in cold weather. Mine is scope mounted and the solution was to wrap it in a USB powered heater pad run by a phone battery charger. I think I paid around $6 on eBay.
I use an Arctic Fox weapon sight laser. I mostly use it for initial set up and when not in use I just put it in my jacket pocket to keep it warm on cold nights. I can't be bothered having to wrap in a heater and have one more thing to plug in. It is fitted to a normal finder dovetail riser block.

Cheers Pete
Attached Thumbnails
Click for full-size image (005.JPG)
163.5 KB58 views
Reply With Quote
Reply

Bookmarks

Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +10. The time is now 06:54 AM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Advertisement
Bintel
Advertisement
Testar
Advertisement