Lasers (again) how powerful is too powerfull

[murray@nsas (Murray)]

The 1mw laser i have been using was not powerful enough.
So I looked on the net for a replacement.
I found a 100mw laser for just $39.00 AUS.
since it was in Australian dollars i figured it was an Aussie site so ordered it (big mistake) next thing i heard was i received a seizure notice from the Customs people wanting an import permit from the NSW Police.
This was obtained and forwarded to Canberra.(with a plethora of other forms). Next thing i know is i received another letter from them wanting me to justify why a 100mw laser was required. I explained to them that it was for attaching to my telescope and was used to point out the object i was observing to the members of the public.
That was a fortnight ago and i have not heard anything back.
I was just wondering what you all thought about a 100mw laser? is it too powerful for practical use? Thanks

[snowyskiesau]

My laser pointer is <20mw and I can't imagine wanting a more powerful one for that purpose.

I wanted to get a laser to experiment with engraving on a CNC mill but getting a license to import such a device proved next to impossible.

[wasyoungonce (Brendan)]

100mW..a bit overkill. 5~10mW is plenty for most amateur..maybe 20mW at a pinch.

Problem with cheapy OS lasers is that they have no or poor IR filtering which can make them very damaging to peoples eyes.

You do not have a "blink reflex" when exposed to these wavelengths (all invisible wavelengths) thus a laser strike on the eye ..you will not automatically have a protective "blink" thus ...damage is insidious..it's too late.

Add to this most near IR wavelengths tends to focus on the retina so..damage can be catastrophic.

I don't think I'm overstating Laser dangers..it's just most laypersons do not understand the real hazards.

[marki]

Way too powerful when you consider that a 5 mw will do the job in most cases. I think there is a restriction on anything over 5mw in any case and would be very suprised if you ever saw the laser you bought. It would come under the catergory of needing a license to operate I would imagine.

Mark

[Ric]

Hi Murray, they are probably wondering why you need 100mW

I find that 5 to 10mW is way enough for astronomical purposes.

Cheers

[wasyoungonce (Brendan)]

I think the limit is 1mW. But, that covers all wavelength LASERs..so that is a little silly.

But this is what we have to live with.

[mswhin63 (Malcolm)]

Have to have licence to own anything over 10mW, this will vary from state to state I believe one state it is 20mW. Anything over that without a licence is considered a prohibited weapon.

$39.00 AU, I would be concern what you get for that as well, You would never get anything like that in Australia. So could be a drop shipper.

[Jen]

mine is a 5mw and it works just fine but a 10mw would be great wouldnt need to go any further i wouldnt think
a 100mw for $39.00 sounds too good to be true

[that_guy (Tony)]

YAY!!! QLD has no restrictions (at least I dont think so) haha i got my eye out on a 20mW finder laser.. why is it that QLD has less strict rules about lasers? I saw a kid at school with a 50mW ones flashing it everywhere..

[steve000 (Steve)]

I own a 50mw that i kinda made my self. I purchased the laser and made my own box, power supply etc. total cost was $59

If you want to know where I got it from i will PM you. totally legal, the company advised that personal details will be retained and provided to the police upon request... so if you go and shine it into peoples faces prepare to be busted. I will post a pic of it as i also intergrated a 5mw red laser for general pointing. they are operated by a series of switches. technically they need to be operated by touch switch only so if you drop it it switches off. i ignored this as I am the only operator etc....

Good luck with the damn customs and their crap.. i gave up with the billions of forms over 3x 0.5mw that were "Tested" at 9mw

[AstralTraveller (David)]

I use a hand-held 30mW for public viewing nights and it is bright enough to be used near lights under a full moon. At a dark sky site it is too bright - you see the laser beam but the sky disappears. I use a 5mW on my dobs scope and that is plenty under dark(ish) skies.

The kid playing about with a 50mW laser is exactly the reason their use needs to be controlled. That thing can cause permanent eye damage so quickly your blink reflex won't save you. It wasn people misusing similar lasers that bought about the need to control them and that in turn created all sorts of trouble for responsible users like most (I hope all) members of this forum.

[mswhin63 (Malcolm)]

I think QLD have done the most sensible thing by making suppliers retain the records, that would be a great idea to make the laws more managable, but dont be surprised if that law changes to suit those that are not sensible though. It usually only needs one incident.

[erick (Eric)]

I have had a 5mW for some years and find that quite adequate for my purposes. I also have a licence in Victoria to possess, store, use this "prohibited weapon". But, as I saw them vanish from Australian catalogs, I thought I'd better get another in case my laser failed. I couldn't buy less than 20mW, from a Queensland supplier, so I bought it. 20mW is more than I wanted and, on testing, is clearly more than I need.... except for pointing to a light-polluted sky for a large group of people.

I have not seen a reason for using >20mW and in most cases, for scope pointing and small group use, 5-10mW would be sufficient.

I will be interested to see how you go justifying 100mW.

[astroron (Ron)]

Originally Posted by Jen

mine is a 5mw and it works just fine but a 10mw would be great wouldnt need to go any further i wouldnt think
a 100mw for $39.00 sounds too good to be true

Good to know it is still working Jen

[firstlight (Tony)]

Originally Posted by steve000

Good luck with the damn customs and their crap.. i gave up with the billions of forms over 3x 0.5mw that were "Tested" at 9mw

A bloke I know who wanted to import some lasars for use in optical tv broadcasting says that products bought from China are rated at a certain level, but are not properly quality controlled and the pot had been set too high, thus a higher level. I think that most of the lasars are able to be increased by turning up the pot.

[OICURMT]

Originally Posted by firstlight

A bloke I know who wanted to import some lasars for use in optical tv broadcasting says that products bought from China are rated at a certain level, but are not properly quality controlled and the pot had been set too high, thus a higher level. I think that most of the lasars are able to be increased by turning up the pot.

This is what I did to modify my laser. It had a 5mW diode but was set and marketed as a 1mW laser. Cranked it to 5mW no problem.

[Jen]

Originally Posted by astroron

Good to know it is still working Jen

Thanks Ron it works like a charm have had it out on a few occasions now with a few friends showing them around the sky they loved it much easier than pointing your finger to a star and saying see this one here and they are looking no where near it

[murray@nsas (Murray)]

Thank you for all your responses.
Probably a 30mW would have sufficed.
But 50m and 100w were the only options.
above 100mW the prices rise dramatically.
for an extra $8.00 I could get the 100mW
Being a member of an astronomy society i thought would not make it a problem.

[GrampianStars (Rob)]

Nice selection here;......
http://www.lasershine.com/wholesale-green-lasers_c774

[mswhin63 (Malcolm)]

Originally Posted by GrampianStars

Nice selection here;......
http://www.lasershine.com/wholesale-green-lasers_c774

You can imagine the government and customs defining importing lasers as a weapon when you see their advertising, "A laser can lignite a match"