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What can be seen from 5+ miles?

K

Ken Hudd

Member
Joined
Dec 19, 2018
Messages
30
Points
8
What type of wattage and lense assembly from a handheld laser is needed for this in a remote heavily forested mountain area, if your friend is 5 or so miles away, that he can easily see with the naked eye? My survival 2.2w blue 445nm with a g2 lens could easily be seen at 2 miles, with the beam 'about the size of a golfball'. His house is roughly 5 miles as the crow flies, and on a remote hill, easily seen from my position, with no houses or lighting sources in between.
 





Ken Hudd said:
What type of wattage and lense assembly from a handheld laser is needed for this in a remote heavily forested mountain area, if your friend is 5 or so miles away, that he can easily see with the naked eye? My survival 2.2w blue 445nm with a g2 lens could easily be seen at 2 miles, with the beam 'about the size of a golfball'. His house is roughly 5 miles as the crow flies, and on a remote hill, easily seen from my position, with no houses or lighting sources in between.
Click to expand...
You've left out info therefore one can only guess at what answer you're looking for.
Guess 1: from your friend's point of view looking directly at the laser there's nothing you need to do. 5mW will be visible.
Guess 2: from your friend's point of view looking at the terminated spot I suspect the spot would be visible.
 
steve001 said:
You've left out info therefore one can only guess at what answer you're looking for.
Guess 1: from your friend's point of view looking directly at the laser there's nothing you need to do. 5mW will be visible.
Guess 2: from your friend's point of view looking at the terminated spot I suspect the spot would be visible.
Click to expand...
I would call him and then aim on top of the hill above his house-it is all his land. I don't want to risk going any lower, as just a flash leaves a perm. spot on your retina. Dr Gas had to use lasers on my wife's ruptured blood vessels over and over-those spots were always there. Here in the east the relative humidity is always above 65%, even in winter. So you always have a distinctively perfect beam. With my Survival 2,2w, I had to walk back to the far side of a field to shoot over a treeline toward the road my brother was on (on the phone with him) which was about two miles away. He saw the beam very clearly going across the sky about a thousand foot up. So did a large number of people coming out of the church, which were shocked at this beam. Of course no one could see the source of which it came, only "a bright blue beam about the size of a golf ball going across the sky." My uncle there relieved them, saying it was me. Now this is about two miles straight in distance in a very remote and humid environment with a g2 lense! But they said the beam continued on above Clark mountain, which is about three miles away.
 
You can research this question yourself.
Key words: laser divergence, inverse square law, diffuse reflection

If you just want to tell a story, bring some photos next time so we can see :)
 
Ken Hudd said:
I would call him and then aim on top of the hill above his house-it is all his land. I don't want to risk going any lower, as just a flash leaves a perm. spot on your retina. Dr Gas had to use lasers on my wife's ruptured blood vessels over and over-those spots were always there. Here in the east the relative humidity is always above 65%, even in winter. So you always have a distinctively perfect beam. With my Survival 2,2w, I had to walk back to the far side of a field to shoot over a treeline toward the road my brother was on (on the phone with him) which was about two miles away. He saw the beam very clearly going across the sky about a thousand foot up. So did a large number of people coming out of the church, which were shocked at this beam. Of course no one could see the source of which it came, only "a bright blue beam about the size of a golf ball going across the sky." My uncle there relieved them, saying it was me. Now this is about two miles straight in distance in a very remote and humid environment with a g2 lense! But they said the beam continued on above Clark mountain, which is about three miles away.
Click to expand...
I agree with RA_pierce. Photos next time please.
 
yeah... a lot of misinformation.. No cameras on those fones?? .
I do not know what to make of this:

'Dr Gas had to use lasers on my wife's ruptured blood vessels over and over-those spots were always there '
If this thread is some kind of joke... shame on you!!

No laser that WE can afford will make ANY 'burns' on a retina at that distance no matter how long you looked at it.

MAYBE if looking at the source with a telescope or binocs it would be uncomfortable. Dont get me wrong -- there are 2 kinds of this info.
Some may be exaggerated to be on the safer side. But at some point. 'We know the sky is not falling' or So no Cry Wolfe.

''people coming out of the church, which were shocked at this beam. '' SHOCKED!!! REALLY?? == Did they think it was God?

TMI to be real.
army AND navy? wow --srsly .thank you for your service.

'Rickrolled'???
where is Chris when we need him?
 
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