Can a 5 mw green laser be used outside during day time? At what range?

Hello everyone!

I have a small problem. I am going on a trip to the Himalaya in 3 days to take measurements of river systems, and I would like a laser level which can be used to shoot a point which can be seen during the day. As I only have a few days, I doubt I have time to get some modified laser. The laser levels they have at Home Depot all have a self-proclaimed range of ~100 feet indoors, and outside, closer to 20. They are all red lasers. I need something that I can see at at least 150 feet. Preferably 300 feet. My thought is to buy a green laser at Fry's and zip tie/epoxy it to a level, then calibrate it with scope.

Will a Fry's Electronics green laser have a visible dot outside at these distances? If not, how far will I be able to see the dot?

Thanks for any advice.

Sean

the dot should be visible, IF you have good 20/20 vision and the sun is not directly glaring you in the face.

I am going to holding the ruler the dot will be hitting. The dot should be 2 feet above my head.

you will see it just fine under those circumstances.

To clarify, there will be a dot from a 5 mw green laser at 300 feet in daylight if I am close to the point, which I can see just fine?

yes.

My only concern is that I assume you are taping the button down on a pointer, it may well overheat.

They are made to run at brief intervals.

Second question: Can a 5 mw green laser be left on for an extended period? i.e. tens of minutes? Will it go until the battery dies, or will its internals fry?

Ok, that is good info. I will have a partner who can press the button. That concerns me a bit as I would like to not have to adjust the level, but it can be done. I will just have to place the button directly over the monopod which will be hold the device.

Also, looking for something I can buy as fast as humanly possibly, I have found very little. An Alpec 5 mw at Fry's for 70 and a Radio Shack brand one for 53.

I could also get one over nighted from Amazon. For a similar price, if they have any decent brands. They have HDE, MPO, MiracleBeam, Instaspark, Shoptronics, more... including in higher powers.

What brands are good? I assume there is substantial variation? Keep in mind, I am more concerned with having this fast that getting the best deal.

If you have the time, I would suggest you order a 5-15mW pointer from a reputable company.
Z-bolt has a few constant on green pointers:
Z-Bolt® BTG-2S plus Green Laser Star Pointer - 5 Mile Range, 3 Finishes, Visible Beam
Edit: Z-bolt has cheaper options but this one I linked to is good for hands free use.

And Novalasers has the best prices on >5mW handheld greens.
X15 Compact Portable Laser - X-Series - Novalasers Inc.
You can also get a 5% discount when you use the code WARP5 at checkout.

15mW will be much more visible in the day and NOVA tends to send out units that are ~5% over powered... so that's extra brightness! I would recommend the X15 + TNT 1-2 day shipping. The price for the power and quality cannot be beat.

Some problems that you may have:
Green lasers (especially the cheap ones) have TERRIBLE alignment. The beam will typically exit the aperture 4-10 degrees off-center. This will make it difficult to align anything without adjusting the orientation of the laser body to compensate.

As far as the duty cycle goes, a 5-30mW green laser is fine for continuous use. I have never had overheating problems with a low power pointer.

Such good advice. I wish I had thought of all this a week ago. have you ever heard of Alpec or anything on Amazon? Trust me, I believe you when you say it is not ideal. I am 3 days from a flight to Thailand, and after I receive the pointer I still have to get it attached to a level. If I do not have it Thursday, it has no value at all, no matter how much better it is.

I looked up Alpec pointers on Amazon.com.
Never heard of them before. They look like they may be ok.

If you really want something reliable and fast at a good price, I would either get the NOVA pointer or a cheap z-bolt 5mW and overnight it.
I've had bad experiences with generic brands and if you're going to pay extra for overnight shipping you may as well get something from a known good company.

Another thing to consider is the laser's divergence. You will want a pointer with the lowest divergence possible so that the beam will stay small and tight over a distance.

DO NOT BUY A GREEN LASER FROM FRYS.

There laser thats green is 5mw, and 99.99$.
Its WAY over priced, the 12$ one I got from ebay was more powerful but less quality.