Safest maximum mw for star pointing

I currently have a 50mw 532nm I use to assist in framing the night sky with my camera but I want more power. I was thinking of making a dedicated 445nm to replace the greenie but I would like to build a good burner too, im about to build a 1.5w but just for burning. But then I read a post that said 1w was ok for night sky use, I also saw a laser light show kit a dj built for indoor use that combined 4 445nm diodes into a 4w beam, now 4w indoors at a night club sounds like a lawsuit to me. But it got me wondering, so this if for people with lots of experience. If you were to go outside at night to show some super model a laser of yours, whats the max mw you would show off?

Well of coutse if there's a super model involved... I'd bring the most powerful laser I've got

10,000 mW .....the way I see it as long as you are not being irresponsible with your use of the laser, then any power is fine to point at the sky. AFAIK we don't have any handhelds that can vaporize the atmosphere so you're good....if you do, however, I would like to ask you one question.....

Can it pop balloons?

The greenie pops balloons just fine but I want to try drawing on wood hence the 1.5w beast. But I wanted to make sure 1.5w was ok for your eyes with star pointing, I may still build a low mw 445 because simply, 3 lasers are better than two....

If you want a low mW blue build, get the Osram PL450B, which is a single mode low power 450nm diode rated for 80mW. That way you get a pretty beam instead of a square.

YOUR thread title mentions stars and safety- you stray away from that quickly- no stars will be harmed by any lasers you can get.

star pointers need only to be seen- 5-50 mW (not Mw or w or mw-or mWs-
any more make seening in the dark harder. All it needs to do is point...


No offence ..but I think you need to spend some time reading here ---

its hard to answer your questions- and there are few - one-laser- does-all..

just be sure no aircraft are near your stars-


gl hk

hakzaw1 said:

YOUR thread title mentions stars and safety- you stray away from that quickly- no stars will be harmed by any lasers you can get.

star pointers need only to be seen- 5-50 mW (not Mw or w or mw-or mWs-
any more make seening in the dark harder. All it needs to do is point...


No offence ..but I think you need to spend some time reading here ---

its hard to answer your questions- and there are few - one-laser- does-all..

just be sure no aircraft are near your stars-


gl hk

Click to expand...

Maybe my greenie isnt really 50mw then because its a pain to find though my viewfinder and I have nice lenses. But I do a lot of painting with light using a speedflash, im usually seeing one big spot at night from that already lol.

What Hak said, if you live near an airport as I do, it is just a matter of common sense
to keep the beam below tree height...one mistake isn't worth 5 or more years in jail.
If, however you live in the boonies, I don't think you have a lot to worry about.

Personally, I would find 1.5 W of 445 massive overkill for star pointing. 660 nm lasers
have much better beam specs and would help keep the eyes adjusted to the darkness.
250 mW always worked just fine for me, even with moderate light pollution.

Be careful

windrider said:

Maybe my greenie isnt really 50mw then because its a pain to find though my viewfinder..

viewfinder on camera or are we talking about a telescope-??
I would think if the laser were properly mounted on your telescope that would be N/P


and I have nice lenses. But I do a lot of painting with light using a speedflash, im usually seeing one big spot at night from that already lol.

Click to expand...

*******
I have some 'painting' ideas to do with long exposure- I have a huge oak in my yard and wanted to do green laser all over the leaves and grassy area & red for the trunk and main branches of the tree.
:wave:

If you want to point at stars and be safe, green is the way to go.
In my opinion, 50mW is just right. A high power 532nm or 445nm laser will work but the brightness of the laser may ruin your night vision.
I have a 10mW and 50mW green pointer that I keep in my camera bag. I set one up on a tripod, point them at the object (or in the vicinity of the object) I want to photograph/observe and it makes aligning my camera or telescope much easier.
The 10mW is a little harder to see through the viewfinder/finderscope but the 50mW works very well.

The reason green is ideal is the fact that the human eye is more sensitive to green wavelengths than any other color, which means you can use less power to get a brighter beam.
Another advantage of green lasers is that they have pretty good beam characteristics for pointing purposes. The common 1W+ laser diodes have rectangular beam with a wide divergence angle.

Ibuprofen mentioned red lasers... I like the fact that red wavelengths do not affect night vision as much but the low brightness of 660nm light makes it difficult to use as a star pointer.
I recently put together a 635nm 75mW laser (single mode) for someone else. It is just bright enough to be used as a star pointer, it is very stable, the divergence is very low, and the red wavelength makes it "soft" on the eyes.
A single mode 450nm laser might work equally well but my eyes don't like looking at 450nm lasers for extended periods... it throws off my color perception of greens and blues and makes my eyes feel strained.

In fewer words, I recommend 50mW 532nm or 75-100mW 635nm.
Below is a photo of 75mW 635nm and 10mW 532nm aimed at the Pleiades star cluster.

If I was trying to show off to a super model? I would probably not worry about the laser so much and pay more attention to the girl.
Hope this helps... gotta get back to work now...