A Unique Use for Lasers

Ok, I went ahead and ordered that laser. Hopefully it will work!

Anybody have any thoughts about using a 'star' diffraction lens to create a bunch of dots instead of a smooth light. Would this create a good sense of depth and clear silhouettes over longer ranges?

I believe most commercial diffraction gratings are made so that the angle of diffraction is far too large to be useful. You are going to hunt them at 100m, so it defeats the purpose if the dots are spread out over a 30m radius.

Gratings make it a lot harder to perceive the distance of whatever is being illuminated. The pattern has a 3D confusing effect (at least on me).

I have a 200mW 650nm. I do use it as a flashlight sometimes (with a diameter of 2-3m), it's pretty good at 10m.

I could take a picture tonight targeting a tree which google maps says is about 40m away from my window. I'm in a city so there's a lot more overall lighting around here and there are no pigs to test

Hey guys,

Got my laser in!!! 200mW 650nm from Lazerer. Very impressed with the build quality. Beam is clearly visible when focused to infinity at night (looks like it's going to infinity too).

At 180yds with a 6-7ft spotlight you can make out the details as well as you need to. at 100yds I easily read a 1-2ft non-reflective sign with binoculars.

I'm really impressed. I think this will be more than enough illumination. Now I need to make a gun mount for it and go hog hunting! We'll see if the little rascals can actually see it or not. Should be interesting, I'll keep y'all posted.

~James

P.S. Thanks for the comments on the diffraction grating. I've given up on the idea now that I see how well this thing illuminates. Also, kudos to Lazerer for getting this to my door in less than 10days!!!

I take it where you're hunting it's legal to use lights? A lot of places make it illegal to use lights to "stun" animals like deer. This may or may not infringe on that law if one applies. Also "lazing" wildlife may indeed be consider cruelty to animals. Much like shooting a deer in a certain spot is considering cruel as it allows the animal to escape and live a horrible life.

@Digital: Interesting points, I've thought about them before. In Texas it is legal to hunt anything but deer with spotlights. Feral Hogs are considered an invasive species and can be hunted by any means except poison (not because they are against poison, just because it's nonspecific). Actually the most effective, and recently legalized, way is shooting them from helicopters by the hundreds!

Also, cruelty to hogs is not even considered. In fact, many farmers will shoot them in the gut specifically so they wander off and bleed out somewhere so they don't have to deal with the body. Although it is definitely a consideration of mine to take game consistently and effectively. So I have no interest in the animal suffering any pain. Not only are hogs less sensitive (ie no pain) to 650nm than humans, but with the laser spread out to a spot the illumination striking the retina is millions of times less than if focused. In fact, it would be easy to argue that at distance and spread out a 200mW is easily eye safe. So it's really not a problem.

I know for a fact that turkeys can not only see a red laser but I think they can feel it! and oh boy does it get them to move!

If hogs would react the same way, then possibly they can get swept into your line of fire?

so when's the bbq?

mmmmmm Bacon wrapped... Bacon!

This has by far been one of the most interesting threads I have ever read on just about anything. Science and Hunting and Eating combined. Hell Yeah!

GreenForce82 said:

mmmmmm Bacon wrapped... Bacon!

This has by far been one of the most interesting threads I have ever read on just about anything. Science and Hunting and Eating combined. Hell Yeah!

Click to expand...

drinking. you missed drinking in this. I'm sure it fits in somehow!
here! hold my beer and watch this .......

Damn, I did...

"Wha Shoot, Haw culd I ah miessd dat!!!"

But seriously, I do not advocate drinking and firearms, or lasers for that matter. But drinking and bacon or other yummy pork products. AMEN to that Brothers and Sisters!

Ok, long time, but I'm back.

Here's the deal. After fiddling with ways to effectively mount it, the laser works...but not quite like I would like.

Distance and power are not obstacles with this laser, but it seems like the animals may be able to see the source of the laser when pointed at them. This effectively makes it a compact spotlight (also useful, but not what I was after).

Part of the problem with mounting is that when focusing the lens is not mounted perfectly in line with the laser so the spot rotates off axis as the laser is focused. Not a problem if free hand, but a big problem when mounted to the gun. The solution I came up with is to friction mount it in a PVC pipe of appropriate length. When the spot size is selected for a given range the entire housing can be rotated back into alignment.

Would it be possible to use this housing and mount a new 808nm or 780nm diode in it? I could modify a digital camera to look through the scope for me and essentially make a decent night vision device. Thoughts on wavelength and or ease of swapping out the diode for a noob?

~James

P.S. Laser spotlights are awesome. Having a lot of fun with this thing, just wish it was eye safe.

Welcome back Good to hear your experiment was partially successful at least.

It sounds like the hogs can see the light as its so concentrated much like humans can weakly see up to about 850nm if its bright enough. I have an 850nm 3 watt LED illuminator on some night vision equipment and when its pointed at you, you can pick up a faint but distinctive red glow.

I have played with some low powered (~100mW) 780nm laser diodes and I can see a faint red spot reflecting back from what they are pointing at with my naked eye. You really need to be careful with these wavelengths and wear eye protection. I once mistook a 780nm diode and had sore blurry eyes for a few hours.

There are plenty of off-the-shelf 808nm and 850nm infra red illuminators designed for use with night vision equipment. You can also get off the shelf night vision scopes, this may be the easiest way to do it. Ill find some links and post them.

Aus, I wish I could afford a night vision scope, but I just don't have it in the budget. Same with the pre-fab IR illuminations. I figured the same thing it must appear as a dim light to them, Deer and hogs both respond the same way, they look confused and then wander off into the night.

Still thinking of removing the IR filter from a pawn shop digi cam and scope mounting it. Then replacing the red Diode with an IR diode from a DVD burner. I figure I can pull it off for about 25$.

Any thoughts on what diode or am I even making sense?

The DVD burner diodes are usually fairly low power (75-150mW) and are semi-visible to the human eye. I think 808nm would be better - you can get high power diodes cheap on ebay as they are used in green laser pointers (frequency doubled in a crystal) among other things. You can get 500mW to 1 watt diodes for $15-$20 or so if you look around.

I converted an old digital camera to IR by removing the IR filter and that works fine, although it doesn't auto focus properly (apparently replacing the IR filter with a piece of plain glass the same thickness fixes this).

The problem you will have with a webcam is low resolution. Also how are you going to mount it at the scope eyepiece and display it? The scope will end up being 8" longer than it is now. Iv'e seen people use viewfinders from old video cameras to make their own night vision gear using a webcam, just not sure how to practically mount it in front of a scope! You also have to think about recoil wreaking everything or throwing it off line. What caliber are you using?

OK, I may try to pick up an 808 diode somewhere. Then again I may just stick with the red and call it good enough. As we saw on the first page, camera's pick up IR or even Red better than the naked eye. So, I may just mount the unmodified digital camera and keep the light level lower than the naked eye can appreciate when aiming at the animals and use the increased sensitivity of the camera to my advantage.

Thinking about using a pawn shop digital camera $20 for the camera. It will add a few inches to the overall scope length, you are right, but I can live with that. Hard to explain the mount I intend to use, but I do have a plan that will result in a good consistent mount. Most digital cams these days are relatively shock resistant, even with the stout recoil of my12ga shooting slugs.

I will be sure to post pics when finished.

Do you think I could modify a greenie to serve my IR purposes, or would that not be cost effective?

Well the conversion from IR to green is only about 20% efficient or so. So a 30mW green laser will have a 1.5Watt 808nm diode in it. You need to mount a lens in front of it though, not sure if you can just remove the crystals in the middle and change the lens, I suspect it may be too far away from the diode. Has anyone here done it I wonder?