First laser for guiding in the forest and star pointing

[DMAN008]

Hello,

I am new here. I would like to purchase my first green laser. I have a few questions:

I am looking at the 30mw range for pointing out cryptic animals in forest trees during day hikes, and overall impressing my clients. Also, I would like to do some amateur star pointing to help others find constellations. 2x AAA models are what I am looking at.

I am looking at a 30mw laser pointer as of now. Is this sufficient? or is this overkill? is 5mw too little? is 50mw too much?

Finally, if you deem 30mw to be perfect for my use, which company in your opinion offers the greatest value for their respective quality?

Thank you very much! I hope to place an order soon!

 

[RA_pierce]

Hi and welcome.

30-50mW should be perfect.
For star-pointing with a 4+ person group, 50mW should be just the right amount for an easily visible beam that is not overwhelming.

If you are looking for a low price, but good quality option, I would recommend Optotronics.com. They have some decent pointers.

If you are looking for a higher quality option (with higher prices), check out Novalasers.com or Dragonlasers.com.
Novalasers offers a 10% discount when you enter the code WARP5 at checkout.

If you just want something cheap that will do the job, many here will recommend O-like.com.

Edit: It may be worth mentioning that a green laser at more than 5mW has a good chance of scaring off most animals and birds.

 

[DMAN008]

Thank you so much!

That is very helpful information.

How about for pointing at animals in trees for daytime use. Will 50mw produce too big of a dot/ too brilliant of a dot? or will it be a good choice?

Like wise, will a more powerful laser, say 100 mw be overkill for either of these applications?

Thanks again!

 

[Meatball]

I would not advise that you use a laser for animal pointing if the laser is > than 5mw. If you must.. I recommend a 1-5mw greenie pointer.

Otherwise, I might recommend a using a flashlight, or a big pointy stick...

Lasers will damage animal eyes too...

 

[Hemlock_Mike]

Most of the critters in my back yard don't seem to care about my lasers. They haven't felt CO2 yet !!

HMike

 

[RA_pierce]

50mW should be pretty visible during daytime over short distances.

100mW is definitely overkill. In my opinion, 50mW is the perfect brightness for pointing applications. 30mW would be more conservative, but still effective.
More than 70mW is very bright and is not very comfortable for dark-adjusted eyes.

Keep in mind that if you go with Optotronics, Nova, or Dragon, your laser may be 10-20% over-spec (a 50mW rated laser could actually be 55-60mW or a 30mW rated laser could be about 35-40mW). Also, Optotronics pointers are not IR filtered, so the output will contain green and infrared, which will skew the actual green output power measurement.

If you wish for something that is at or close to the rated power, all the companies I have listed are known for good customer support. I am sure they would not mind providing a unit that will meet your specific needs, should you ask.

 

[BKarim]

10mw should be great.
i have my 10mW green pointer GLS5ON with constant/momentary ON switch from www.apinex.com since 4 days and i am totaly satisfied.
it is the same model as z-bolt one but 2 times more powerful and cheaper

at 50mW the dot is way too bright. i can't look at my 10mW dot indoors... i can see the dot on trees daytime whitout problems (assuming the tree is not 100m away...)
beam very visible at night like a giant light saber

 

[DMAN008]

what do you mean exactly by 'not IR filtered.' Is this good, bad, neutral?

 

[RA_pierce]

what do you mean exactly by 'not IR filtered.' Is this good, bad, neutral?

An IR filter filters out infrared light (IR). DPSS lasers use an IR diode to pump crystals in order to create light at a different wavelength (color). Some of the IR will "leak."
Personally I think it's not a big deal unless an accurate power measurement is needed. I would say it's "neutral" although I prefer a nice "pure" green output.

In some cases IR leakage can be dangerous, but it depends on how much leaks and the divergence angle of the IR beam.

 

[Jaseth]

Please listen to the warnings about pointing at animals - unless you are very far away, anything over 5mW is dangerous to the eyes of humans and most likely also a lot of animals. To maintain optimal safety for the animals, your clients and yourself, I would suggest getting a green laser between 1mW and 5mW.
Another thing to note is that "5mW" lasers you purchase may be far more powerful than what they are labelled as, and therefore dangerous, if purchased from cheap dealers. You should go with a trusted company such as the ones RA_pierce recommended.

For night time star pointing, and pointing at objects (trees, mountains, whatever you need) far away, I would suggest a 30mW green laser. Personally I do not like powers exceeding this for pointing at stars since the beam itself becomes bright enough to ruin my night vision.
At this power (30mW), it should only be used for pointing at objects and never at living creatures or near vehicles of any kind (not pointing at vehicles also applies for 5mW and weaker though).

So basically.. you should probably get 2 good quality lasers - one 5mW for general pointing and one 30mW for star pointing and pointing at objects far away.

As to IR filtering - if you get a high quality lasers, there is usually a filter, and if there is no filter, the IR leakage is most likely quite insignificant with 5mW and 30mW lasers, and far from as dangerous as the green output.

Seb

 

[BKarim]

this is untrue. IR have same thermal effects than green (warm objects emit IR radiations).
IR is at least 300mW for a 30mW green pointer so i think IR filtering is MANDATORY.


in the forest and for star pointing a 5mW should be enough so you can safely buy a 10mW

 

[Arayan]

Also, Optotronics pointers are not IR filtered

But also portable RPL lasers by Optronics not have IR filters? :undecided:

 

[Jaseth]

this is untrue. IR have same thermal effects than green (warm objects emit IR radiations).
IR is at least 300mW for a 30mW green pointer so i think IR filtering is MANDATORY.

The 808nm pump diode will be a lot more powerful than the green light that is emitted, yes, but the power of this pump diode is what creates the 532nm through the frequency doubling of two crystals, meaning most of the IR disappears in the process. In a good quality green laser with well aligned crystals, the IR leakage will be very small compared to the 532nm output. Filtering IR only becomes relevant when you have a high power unit and think that goggles blocking the 532nm wavelength are enough to protect you, while the IR leakage at a power such as 200mW of green may be enough to cause damage on its own.

Furthermore, IR does not have the same "thermal effects" as green. All wavelengths have different thermal properties. For example, long wavelength IR such as that from a CO2 laser (about 10000nm) will melt glass rather than shining through it and getting reflected. Blu-ray (405nm) will burn much more effectively at the same power than other visible wavelengths, and is the only commonly owned hand held laser which can easily burn light materials at low powers.

in the forest and for star pointing a 5mW should be enough so you can safely buy a 10mW

If you want effective star pointing where the beam is quite visible to several people around you even when the air is quite clear of particles, 10mW will not be enough. 30mw is usually the preferred power for this.

Seb

 

[BKarim]

here's what sam's laser FAQ says for a 5mW pointer:


Do NOT remove the IR filter: A substantial amount of the 808 nm pump light can leak through to the output (10s of mW or more which is potentially dangerous) and this is nearly totally invisible and swamped by the green output. Some totally invisible IR at 1,064 nm from the vanadate lasing process also leaks through the output mirror and its power may be similar to that of the green output! The IR filter is typically a greenish piece of glass buried inside the collimating optics but on some models, unscrewing the end-cap also removes the IR filter. The risk of the additional IR isn't worth the very slightly increased green output that may result. It's best to avoid these models entirely or somehow make sure that the end-cap can never be left off accidentally.

Some/many imported green pointers don't even have IR filters. This of course is a serious safety hazard. But, it also may result in bogus readings for green output power. So, someone can claim "300 mW from this green pointer" without saying that 299 of those mW are IR!

 

[Jaseth]

The "10s of mW or more" is only leaked in high power units or units where the crystals are badly aligned. In a high quality 5mW units, the IR leakage is usually <1mW. The IR is also less collimated and therefore less hazardous.

The readings where IR severely messes up the power which is measured tend to be on LPMs with optical heads, where the unit has to be set to measure a specific wavelength, and 20mW of IR may therefore show up as 150mW of green.

Low quality DPSS lasers and high powered DPSS lasers do emit dangerous amounts of IR unless they are filtered, but for what he is asking for, an IR filter is not necessary.

Seb

 

[jander6442]

I have always found that the 30mW to 50mW range of 532nm is either not bright enough or too bight for pointer use. 30 mW outside is ok depending on daytime or night, but inside to bright for common pointing.

50mW is good for most outside applications just a nuisance almost for inside pointing. I would say a good 10mW 532nm for the OP guide pointing would be better. my opinion of course.