Best laser for long distance pointing

[JimBolder]

For long distance pointing, go with a green.

But the crystals in green pointers are temperature-sensitive, so I don't know if they would function properly in the temperatures that you described.

Then again, I don't really have that much experience with high-powered greens.

 

[mikzip]

Hi i ended up buying this one from O Like
400mW green laser torch /focusable/waterproof (Wavelength:532nm Output Power: 350mW) 208$
Had it for about a couple of weeks now.
I am happy about the beam brightness and visibility, but the range is much shorter than i anticipated, the beam seems like it reach about 200 to 300 meter focused as much as possibly, it is impossible to get a visible reflection "dot" on a smaller mountain covered in snow across the fjord about 5 kilometers away.
Maybe it is way underspec? i will eventually get a meter when the $99 ones are availably again.

 

[RA_pierce]

Hi i ended up buying this one from O Like
400mW green laser torch /focusable/waterproof (Wavelength:532nm Output Power: 350mW) 208$
Had it for about a couple of weeks now.
I am happy about the beam brightness and visibility, but the range is much shorter than i anticipated, the beam seems like it reach about 200 to 300 meter focused as much as possibly, it is impossible to get a visible reflection "dot" on a smaller mountain covered in snow across the fjord about 5 kilometers away.
Maybe it is way underspec? i will eventually get a meter when the $99 ones are availably again.

You are overestimating the abilities of this laser.
300mW @ ~1.5mRad is not going to put a visible spot on something 5km out.
Remember that the light has to travel to the mountain and then back to your eyes, so that's a round trip of 10km. Also, sometimes the bright beam will drown out the "spot" on distant objects.
You'd probably be able to see the point of termination with lower divergence and some binoculars.
However, I am positive that any observer on the mountain would be able to see it.

 

[chipdouglas]

Hi I am all new to lasers. I would like to buy a laser
where the beam can be seen on long distances (kilometers)
I am not interested in burning stuff.

I am a little confused with all the options??

Which one would you recommend of these two from O Like?

400mW green laser torch /focusable/waterproof (Wavelength:532nm Output Power: 350mW) 205$
Real 1W 445nm blue Laser torch/waterproof/focusable (Wavelength:445nm output power :900mW) 210$
Or maybe something else in the same price range.

I know that the greenie is sold out for the moment

Some more questions, do i need goggles just to point up in up in the sky, as i understand it, it is only a direct beam-shot in the eye that are dangerous, reflected or not?

I live in Greenland, so i am also concerned about the usability in a cold climate, can I damage the laser to use it in sub minus temperatures? :undecided:

if i point my red dilda and my 96mw green up in the air, the red appears to go farther. but obviously you have to strain your eyes to follow the beam. where as the green beam is clearly visible.

 

[GBD]

A while back I used to have an orange HeNe at around 3mw or so. The beam isn't visable without some fog in the way (or looking down onto the beampath), but the dot did travel very far and had very nice beam specs (although this is a gas laser, not exactly portable without some intricate PSU/host). This is what I would use if you where trying to have a small dot at a very far distance (couple a HeNe with beam expanding optics and Im sure it will be even better).
More or less useless for beam visability (can kinda see it sometimes), but the dot is great.

Cost wise and effectiveness, as already said in the thread, you should get yourself a 200mW+ green and if you want some extra distance get beam expanders for your laser. (although these type of optics cost a chunk of money, good ones 200$-300$ or more even).

 

[mikzip]

I would like to know more about beam expanders, if this is the way to reach my goal

 

[DJNY]

I would like to know more about beam expanders, if this is the way to reach my goal

This also may help you a bit
http://laserpointerforums.com/f55/jetlasers-gb-3-closed-58971-8.html#post862985

 

[chipdouglas]

or for around 80 bucks you could get one direct from dragon lasers. a beam expander that is.

michael.

 

[mikzip]

Maybe i misunderstand something but for me it only looks like it make the beam thicker, i wouldn't think that it made it reach a target longer away??

 

[GBD]

Maybe i misunderstand something but for me it only looks like it make the beam thicker, i wouldn't think that it made it reach a target longer away??

With it your trading something, beam thickness for lower divergance.
Divergance is the spread of the beam itself, and with a beam expander you lower this divergance by starting out with a wider beam.

Yes it will expand you beam, but it will also make the spread of it alot lower then without it. (this is why it will go farther and stay tight)

So you trade away a small beam, some beam visability (as the beam is thicker but still the same/less power from optics losses) for longer distance.

 

[Razako]

Hercules+X10DR
With the beam expander mine can practically hit stuff on the other side of town with a noticeable dot.

 

[mikzip]

I am consider bying a 532nm 600 or 700mw with a 3 or 5 x beam expander from the next GB from Jetlasers, maybe this will give me what i'm looking for?

 

[DJNY]

I am consider bying a 532nm 600 or 700mw with a 3 or 5 x beam expander from the next GB from Jetlasers, maybe this will give me what i'm looking for?

You can´t go wrong with a JETLASERS laser

Their beam expanders also look very promising.