Tigervision handheld NIR device

[PhotonWrangler]

Burlington Police receive a Tigervision night-vision device.

I've gotta wonder how useful this will be for long-range surveillance though. Since the IR LEDs probably don't have much throw, the only way to get any range would be to use a beam-expanded IR laser as an illuminator.

Your thoughts?

 

[LumenHound]

Depends on what you define as long range surveillence.
I purchased some 870nm IR leds from another member (Hubbard-see this thread) and while they are barely visable, they are very narrow focus leds in that at 10 degrees off axis they are down to 50% brightness. They might even be tighter than this. These leds, when massed in a group of 15 and aimed at the same point, can really put some good IR on things 600 feet away to the point that even a lowly first gen+ night vision device gets a very usable image. These leds have very good output.
Is 600 feet long range?

 

[PhotonWrangler]

600 feet is impressive for an LED cluster, although that's coupled with a night vision device. I'm gathering that the TigerVision system uses a regular CCD pickup...?

 

[LumenHound]

I don't think a "$5000.00 device" would use a regular CCD pickup.

 

[PhotonWrangler]

I don't think a "$5000.00 device" would use a regular CCD pickup.

Wanna bet?

:huh:

They're claiming 100 yards, and it looks like the unit has an array of about a dozen IR leds. Everything else about tle specs suggests it's a regular video camera (30fps, 450 lines, 1vP-P into 75 ohms). Even the photograph on their home page looks like it came from a regular CCD video camera.

 

[LumenHound]

It's no wonder they couldn't sell them and ended up giving them away for the good PR it would bring.
I'll bet the 12 volt cordless drill rechargeable battery set-up cost more than $15. A honkin' big 4 inch monochromatic view display also.
I used a 4 inch monochromatic view display device once. I called it the crappy black and white camping stlye TV/AM radio my parents bought back in 1974.

Corporate donation = tax writeoff.

 

[PhotonWrangler]

Bingo, LumenHound. At least they chose an LCD display instead of a CRT. I think the only unique aspect of it is the built-in 2.4ghz transmitter. I'm guessing that the actual NV performance is OK if you're close to your subject, but if you're close, how covert can you be?
:thinking:

 

[LumenHound]

A $5000 product like this might have flown back in the 80's when the $600 hammer and $2000 toilet seat purchases were made but in this day and age it is just ludicrous.

 

[Makarov]

I've tried the Nightview(only indoors tough) and it works and is a lot cheaper($360 in Norway) than the Tigervision.

 

[Hubbard]

Thanks for the positive reviews of my LED arrays Lumenhoud.

I still have a bunch of these left if anyone wants some.

I took some video using these arrays with a Sony Handcam shot in NiteShot mode. I'll post it as soon as I can. An abridge version of the video is this. With the single LED(from the video cam) on a room 20x20 looks like a flashlight is being used, meaning there is a spot that is visible. With the array on, the whole room seems to light up, especially with the bounce off painted walls.

I will get pictures up ASAP.

 

[Doug3581]

I tried doing this some time ago (making various IR illuminators for gen-1 NV).
Bare LEDs don't work very well, because their light ends up short and diffuse. The only way it works very well is if each LED would have a focusable lens on it......

I tried a IR LED conversion of a mag-lite 2-D cell and the focusable head helps a LOT--with the focusable head, you could see the spot at 50+ feet, from just one 830nm IR LED @ ~50mA. (This works GOOD if you have one of these old flashlights, use a resistor in the tailcap to limit the current). -And these LEDs do glow red when powered, just a bit. So they are not invisible.

So then I tried a perfboard with 19 of the same LEDs on it, that just fit in where the regular bezel used to--and the light was WAY shorter. I had them set to run at the same current as the single-LED "bulb". But it did not work well; the light was very smooth, but wasn't really visible at all beyond about 15 feet.

So then I tried a $12 Brinkman Long Life LED light from Wal-Mart; this is a single-white LED 2xAA flashlight with no reflector, not focusable but with a plastic convex lens. It works pretty good as IR, I just ditched the regulating circuit and used a resistor instead. This flashlight/mod works better than the "19-LED setup with no beam focusing" setup did.

Also what you can do for a cheap and nearly-invisible NV light is to take a regular incandescent bulb, and current-limit it somehow to where the filament just b-a-r-e-l-y begins to glow. But then again--this is still not invisible.

I also tried the IR-filter plastic available from Edmund Scientific. They were selling 1-inch squares and 2-inch round pieces; the 2-inch round is 51mm and the lens of a big mag-lite is 52mm, so it fits right in if you remove the clear lens. The plastic appears brown/rust-colored if you look through it in daylight; on the full-powered maglite 2-D at night it glows a dim red. Not anywhere near invisible, but very bright in the NV scope. And focusable, which helps a LOT. Up close, the focused spot is too bright for a gen-1 and you have to set it to flood, but far away, you need that focused spot.

I never did find any cheap way to get totally-invisible IR that would also show up in a gen-1 Russian NV scope. The 830-nm IR LEDs I was using tend to glow red just a bit--you can't see it off-center, but if the beam is pointed at you, you can see them. The 940-nm LEDs do stay invisible to the eye even when powered, but their light is just barely visible in gen-1 NV scopes.

Now I heavily suspect that you can't have a gen-1/2 NV light that isn't also visible to the naked eye. To have light but "stay invisible", you would need a gen-3 scope ($2500+!) and a 900+ nm light source.

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As for the Tigervision, I would bet it's crap.
The only way CCD is good for NV is if there's a MCP-tube in front of the CCD.
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