Cheap astronomy laser

[cpper]

Hi
I want to buy a cheap laser for night use,more exactly to point it to the stars.
I want a briiight,looong beam.
My question is what color and power is the best for this ?
:thanks:

 

[EpicHam]

Hi
I want to buy a cheap laser for night use,more exactly to point it to the stars.
I want a briiight,looong beam.
My question is what color and power is the best for this ?
:thanks:

There is actually a similar thread already up on the same board.

http://laserpointerforums.com/f44/cold-temperature-laser-83099.html


For a BRIGHT LONG BEAM!
Look no further than a 532nm 10mw ish Green Laser.

Thats pretty much the industry standard for astronomy.
Being one of the most sensitive frequency of the human eye , its excellent in terms of visibility.

However, I think a 100mW 650nm Red laser maybe more appropriate since it won't flash out your eyes as much and you can go right back to star gazing faster.

 

[cpper]

Is a 532nm 10mw the same with a 650nm 100mw(i mean brightness and distance) ? It's a very big power difference :|.

 

[EpicHam]

Is a 532nm 10mw the same with a 650nm 100mw(i mean brightness and distance) ? It's a very big power difference :|.

so is your eye sensitivity

 

[DJNY]

https://www.fasttech.com/product/1030000

http://laserpointerforums.com/f52/review-1xaaa-532nm-laser-pen-81863.html#post1175975

 

[ToneLoke]

For astronomy, don't go with anything more than a 5mw 532nm. Anything more will destroy your night vision.

 

[EpicHam]

For astronomy, don't go with anything more than a 5mw 532nm. Anything more will destroy your night vision.

Not really sure why people like to go green.. since at 5mW, the only thing that pen will does really is point at things... but any way...

 

[DrSid]

People go for green, because at 5mW, red does not produce visible beam even with nightvision at maximum, while green does.

 

[ToneLoke]

Actually, my taurus produces a faint beam at night (when looking parallel to it).

 

[tonyt]

My two cents. Buy a $4 ebay 650nm. It will say it is only <5mW but in reality it will be closer to 50mW and will be perfect for your application. Any more power than that and even though it is red you will still loose part of your night vision. Or, go for a 561nm, 589nm or 593.5nm. They will cost you more but I actually find the "yellow" much easier to see against the black sky. Thanks is what I use for astronomy.

 

[firelaser]

LZMN - Mini 650nm 100mW Focusable Red Laser Pointer

here is a low power green LZTN - 532nm 5mW Smallest Green Laser Pointer Key Chain

and a stronger green
LZCS - Classic 532nm 30mW Focusable Green Laser Pointer

basically green is better, unless it is cold then go with red.. and brightness depends if you have night vision and how bright yuo want the beam

 

[tsk1979]

I have a 7$ green laser (rated <5mw but clearly overspec) from dealextreme. Works great for pointing at stars. Beam is slightly visible even in dimly lit rooms.

 

[jimmy009]

Red or green is both good, and just choose which you like better

 

[tsk1979]

Red or green is both good, and just choose which you like better

Even a cheap 5mW greenie is good enough for star pointing. For red you need higher power. So for astronomy, green is definitely much better as our eyes are more sensitive to green light.

 

[EpicHam]

Even a cheap 5mW greenie is good enough for star pointing. For red you need higher power. So for astronomy, green is definitely much better as our eyes are more sensitive to green light.

Its true that at power as low as 5mW , a 532nm green laser will suffice as a pointer under very very low light situations with next to no light pollution.
However , at such power it also limits you to solely pointing.

When you choose a 650-638nm red laser at 100mW+ , besides from using it as a pointer ,you can also use it as a lighter.

 

[tsk1979]

Its true that at power as low as 5mW , a 532nm green laser will suffice as a pointer under very very low light situations with next to no light pollution.
However , at such power it also limits you to solely pointing.

When you choose a 650-638nm red laser at 100mW+ , besides from using it as a pointer ,you can also use it as a lighter.

Actually, that is not good. A high power red becomes a dangerous object, and looking at the dot on a wall, as well as stray hit can cause eye damage. If your purpose is astronomy, its best to go with a 10-15mw Greenie. Having a higher power laser pointer is not always a good thing, unless you want an all in one.