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  #21  
Old 13-09-2014, 11:54 AM
Renato1 (Renato)
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Quote:
Originally Posted by sharpiel View Post
http://m.youtube.com/watch?v=jyaLZHiJJnE

Beams...streams...same, same. Don't destroy the universe!
Oh - that bit. Now I understand thanks,
Renato
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  #22  
Old 13-09-2014, 12:11 PM
Renato1 (Renato)
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Originally Posted by ericwbenson View Post
Five lasers can make five parallel beams, getting them parallel and keeping them there you will find to be <extremely> difficult. But if you could do it to within an angle less then the beam divergence (about 1 mrad or so, which is ~3 arc minutes !!!) then at a distance the five beams will overlap and it will appear brighter. That distance depends on how close you can get the barrels and the beam divergence. Unfortunately that distance might be so far away that the five times intensity gain is swamped by the 1/r^2 intensity drop due to distance, so it may gain nothing.

The beams are not coherent (aka in phase) with each other but for the purposes of scattering off dust particles that doesn't matter.

BTW you can't use a beam combiner for lasers of the same wavelength, you can combine two linearly polarized lasers, but that's it.

Best,
EB
Thanks. Just thinking about it further, the barrels of the laser tubes would have to be parallel, and depending on the placement of buttons and pocket clip, one may only be able to get three and/or four tubes against each other. If three or four tubes against each other produced parallel beams, then one could put bunches of those numbers together.

That said, it all really depends on how bright a 1mW beam is. I have no idea. From memory, a 5 mW beam wasn't all that bright unless one was somewhere pretty dark.
Regards,
Renato
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  #23  
Old 14-09-2014, 12:18 AM
Stardrifter_WA
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Originally Posted by Renato1 View Post
I have no idea. From memory, a 5 mW beam wasn't all that bright unless one was somewhere pretty dark.
Regards,
Renato
Hi Renato

Be aware Renato that some so called 5mW lasers are not actually 5mW, even if they are marked as being such, and that may be why you think they are not that bright. I have a 5mW GL Laser Rifle Sight (which cost $265), and that is definitely bright enough for astro use.

Cheers Pete
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  #24  
Old 14-09-2014, 01:01 AM
Renato1 (Renato)
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Originally Posted by Stardrifter_WA View Post
Hi Renato

Be aware Renato that some so called 5mW lasers are not actually 5mW, even if they are marked as being such, and that may be why you think they are not that bright. I have a 5mW GL Laser Rifle Sight (which cost $265), and that is definitely bright enough for astro use.

Cheers Pete
Thanks Peter,
Your point also raises the interesting issue - as a laser rifle sight it is legal, but if you use it for something harmless to show people the planets and constellations...... then it is doing the same thing as a prohibited weapon!
Maybe you have to keep it on your rifle to keep it legal for astronomy usage?
Cheers,
Renato
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  #25  
Old 14-09-2014, 07:28 AM
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Laser sight is legal (in QLD) IF you have a valid/current firearms license - cost for initial license is around $300 - the laser cannot be purchased without the license - AND you add it onto your license (currently $38.34 in QLD per application or something) AND you have a legitimate requirement for it (which is submitted at the point of application for permit - they are VERY stringent in what is acceptable use - I said Astronomical use, which they approved).

So, no, it's NOT as simple as you think.

The 5mW green one I have (ex-pistol, on license), as Peter says, is more than adequate to illuminate atmospheric particles for you to point at something in the sky.
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  #26  
Old 14-09-2014, 12:24 PM
Renato1 (Renato)
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Quote:
Originally Posted by LewisM View Post
Laser sight is legal (in QLD) IF you have a valid/current firearms license - cost for initial license is around $300 - the laser cannot be purchased without the license - AND you add it onto your license (currently $38.34 in QLD per application or something) AND you have a legitimate requirement for it (which is submitted at the point of application for permit - they are VERY stringent in what is acceptable use - I said Astronomical use, which they approved).

So, no, it's NOT as simple as you think.

The 5mW green one I have (ex-pistol, on license), as Peter says, is more than adequate to illuminate atmospheric particles for you to point at something in the sky.
Fascinating stuff Lewis. Where you live you can thus effectively get a laser as part of a shooting licence, but down here in Victoria we have to pay $160 for a two year licence to own a laser for astronomy use.

I suspect though, that where you live, someone had a lot of discretion about the rifle laser for astronomy use. Could it be possible that someone else making the same application may have it rejected for that usage?

I wonder if the same could be the case in Victoria - in which case shooters pay less for having a laser, than do recreational astronomers?
Cheers,
Renato
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  #27  
Old 14-09-2014, 04:52 PM
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Originally Posted by Renato1 View Post
Thanks Peter,
Your point also raises the interesting issue - as a laser rifle sight it is legal, but if you use it for something harmless to show people the planets and constellations...... then it is doing the same thing as a prohibited weapon!
Maybe you have to keep it on your rifle to keep it legal for astronomy usage?
Cheers,
Renato
Hi Renato,

In WA a GL laser is considered a "controlled weapon" meaning that it isn't illegal to own and use, as long as it is used for a legitimate purpose. I am allowed to use a GL Laser Weapon Sight for astro purposes, and in fact it makes a great finder (as shown in the attached photo). I got the mounting block from Stellarvue and attached the weapon sight to that. The weapon sight is available locally from Arctic Fox in Malaga (Western Australia). I am picking up a new one from them this week. I have to replace the one I gave to my son for his telescope. They are not cheap at $264 but they are very good, as they are very simple to align using the X-Y adjusters.

Astronomy is one of the legitimate purposes, although I also have a rifle licence anyway, so I am good on either front. I did some lobbying in this regard when they first proposed those laws here, and common sense ruled in the end.

However, get caught with one in your possession can lead to significant fines, unless you can prove you had it for legitimate purposes. For this reason, my GL laser rifle sight is always kept with my telescope. I also have a letter from the Minister for Police stating that astronomy is a legitimate purpose. In addition to that, I also keep a copy of a weapons import certificate in my box as well, as I previously imported another GL laser, which I have mounted on my 16".

Please note though, various states have different laws. WA has the most sensible law in this regard.

Cheers Peter
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  #28  
Old 14-09-2014, 04:54 PM
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Quote:
Originally Posted by LewisM View Post
Laser sight is legal (in QLD) IF you have a valid/current firearms license - cost for initial license is around $300 - the laser cannot be purchased without the license - AND you add it onto your license (currently $38.34 in QLD per application or something) AND you have a legitimate requirement for it (which is submitted at the point of application for permit - they are VERY stringent in what is acceptable use - I said Astronomical use, which they approved).

So, no, it's NOT as simple as you think.

The 5mW green one I have (ex-pistol, on license), as Peter says, is more than adequate to illuminate atmospheric particles for you to point at something in the sky.
Ah, its simple for us Lewis. Qld is too strict about everything, it seems. WA have sensible laws in this regard, it is classed as a "controlled weapon" and you can own and use one, without paying any fees, as long as you have a legitimate purpose. Astronomy is a legitimate purpose, as I have a letter from the Minister of Police stating just that.

Last edited by Stardrifter_WA; 14-09-2014 at 05:12 PM.
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  #29  
Old 14-09-2014, 10:03 PM
Renato1 (Renato)
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Quote:
Originally Posted by Stardrifter_WA View Post
Hi Renato,

In WA a GL laser is considered a "controlled weapon" meaning that it isn't illegal to own and use, as long as it is used for a legitimate purpose. I am allowed to use a GL Laser Weapon Sight for astro purposes, and in fact it makes a great finder (as shown in the attached photo). I got the mounting block from Stellarvue and attached the weapon sight to that. The weapon sight is available locally from Arctic Fox in Malaga (Western Australia). I am picking up a new one from them this week. I have to replace the one I gave to my son for his telescope. They are not cheap at $264 but they are very good, as they are very simple to align using the X-Y adjusters.

Astronomy is one of the legitimate purposes, although I also have a rifle licence anyway, so I am good on either front. I did some lobbying in this regard when they first proposed those laws here, and common sense ruled in the end.

However, get caught with one in your possession can lead to significant fines, unless you can prove you had it for legitimate purposes. For this reason, my GL laser rifle sight is always kept with my telescope. I also have a letter from the Minister for Police stating that astronomy is a legitimate purpose. In addition to that, I also keep a copy of a weapons import certificate in my box as well, as I previously imported another GL laser, which I have mounted on my 16".

Please note though, various states have different laws. WA has the most sensible law in this regard.

Cheers Peter
Thanks Peter,
Good to see that one State is sensible. And that's one very nice looking laser and superb sight you have there.

A friend did try using a 5mW laser on rabbits years ago, hoping it would be better than a spotlight. The rabbits were unperturbed and happily hopped away. And that laser is a probited weapon over here, akin to a fully automatic rifle.

Curiously, kids are constantly making prohibited weapons, when they make slingshots.

But oddly, when I recently bought my 15 year old nephew a deadly 35 to 60lb compound hunting bow for his forthcoming birthday - well, not a problem. My nephew kept asking "Are you sure I don't need a licence for this?"

Cheers,
Renato
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  #30  
Old 15-09-2014, 05:53 PM
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Originally Posted by Renato1 View Post
But oddly, when I recently bought my 15 year old nephew a deadly 35 to 60lb compound hunting bow for his forthcoming birthday - well, not a problem. My nephew kept asking "Are you sure I don't need a licence for this?"

Cheers,
Renato
Hi Renato,

I don't know what the laws are in relation to compound bows. It is more likely that they too come under controlled weapons legislation. I have a compound bow too and don't need a licence. However, I believe that a "cross bow" is now a prohibited weapon in WA. Understandable really, as "cross bows" are deadly and are not really a sport weapon. I am surprised that a compound bow doesn't yet require a licence though.

I haven't used my compound bow for a while, as I can no longer pull back the 70lb draw weight, due to a wrist injury.

Cheers Pete
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  #31  
Old 18-09-2014, 12:15 PM
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Originally Posted by Stardrifter_WA View Post
Hi Renato,

I don't know what the laws are in relation to compound bows. It is more likely that they too come under controlled weapons legislation. I have a compound bow too and don't need a licence. However, I believe that a "cross bow" is now a prohibited weapon in WA. Understandable really, as "cross bows" are deadly and are not really a sport weapon. I am surprised that a compound bow doesn't yet require a licence though.

I haven't used my compound bow for a while, as I can no longer pull back the 70lb draw weight, due to a wrist injury.

Cheers Pete
Hi Pete,
Yes crossbows are banned in Victoria too - which I thought strange, as the ones typically sold here were a lot less powerful than compound bows. All the Ebay ads say that no licence is required for a compound.

Can't you turn the poundage down on your 70lb one? I've got a 57 to 70lb one which gives me a work out drawing 57lbs. I've also got another one which I use more often at 50lbs - since I don't wreck arrows as much with it.

Though I'm having more fun with a cheap recurve riser, long bow.

I bought them because I was getting frustrated with all the foxes around here walking around like they owned the place, and wanted to take pot shots at them. Strangely, I haven't seen one since I bought the bows.
Cheers,
Renato
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  #32  
Old 18-09-2014, 12:56 PM
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Originally Posted by Renato1 View Post
Hi Pete,
Yes crossbows are banned in Victoria too - which I thought strange, as the ones typically sold here were a lot less powerful than compound bows. All the Ebay ads say that no licence is required for a compound.

Can't you turn the poundage down on your 70lb one? I've got a 57 to 70lb one which gives me a work out drawing 57lbs. I've also got another one which I use more often at 50lbs - since I don't wreck arrows as much with it.

Though I'm having more fun with a cheap recurve riser, long bow.

I bought them because I was getting frustrated with all the foxes around here walking around like they owned the place, and wanted to take pot shots at them. Strangely, I haven't seen one since I bought the bows.
Cheers,
Renato
Hi Renato,

Yes, it is strange that crossbows are illegal yet compounds are not, as in the right hands, a compound is more dangerous that a crossbow. However, from the perspective of a beginner, a crossbow is much too easier to use, whereas, the compound requires a much higher level of skill.

From that point of view, I doubt most people who would use a crossbow, for nefarious purposes, would bother developing the skills to use a compound. Maybe? I don't have the mind of a criminal, so I don't know what their motivations are anyway.

I have backed of the draw weight of my compound, but unfortunately, it is still too much to draw any more. I had two severely broken wrists, which makes it difficult to hold and draw nowadays. I have tried a lower draw weight compound as well, but due to some nerve damage I have a slight shake now, which makes it rather interesting trying to hit the target with any accuracy. I really should sell my compound bow, it is of no use any more.

Foxes are wily b's, so I am not surprised they didn't hang around after you got your compound bow. I used to shoot them on the farm, but they were always hard to get.

Cheers Pete
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  #33  
Old 18-09-2014, 09:33 PM
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Renato, hypertune those lasers, and you can vaporise the foxes

I dislocated my shoulder a few years ago. I could not even cock an air rifle at one point it was that bad, let alone draw a compound bow. I know the feeling all too well.
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  #34  
Old 18-09-2014, 09:46 PM
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Renato, hypertune those lasers, and you can vaporise the foxes

I dislocated my shoulder a few years ago. I could not even cock an air rifle at one point it was that bad, let alone draw a compound bow. I know the feeling all too well.
And just how do you hypertune a laser Lewis
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  #35  
Old 18-09-2014, 09:58 PM
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I wasn't being literal Pete It does bring us full-circle again
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  #36  
Old 18-09-2014, 09:59 PM
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  #37  
Old 18-09-2014, 10:06 PM
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I wasn't being literal Pete It does bring us full-circle again
I know. The word hypertuned is such an overused word that actually has no real meaning. Well, not according to any of the dictionaries I own, it doesn't. And, to be clear, I do know you can tune a laser though, but not just any laser.
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  #38  
Old 18-09-2014, 10:09 PM
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Your response is ultra premium
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Old 18-09-2014, 10:15 PM
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[QUOTE=LewisM;1118541]Your response is ultra premium [/QUOTE

I love the use of your words Lewis, hmm 'ultra premium', now I wonder what that is supposed to mean, in this context Or, maybe I am not use to such superfluous words.
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Old 18-09-2014, 10:16 PM
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Seeing we are talking death rays, I decided to get the licensed zapper out today to play devil's advocate with my fluorites and FPL53's.

ANYWAY, I found out that even the scattered reflection of one of these puppies off a matt painted wall backdrop is enough to darned well cause blurring of the eye for a while.

They are that bright.

I admit to making dew-dew-dew sound effects... because I am an imbecile.
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