Night Vision Odd Question About PVS 14 and "Temporary Artifacts"

[Strykervet]

So I finally got to test out the PVS30 and PVS14 mounted to the spotting rig together. The PVS30 worked fine and I got the same groups at night as I did during daytime. Only at 100y, again, but I to work with what's available and I was just zeroing and getting familiar with some new stuff.

So the rig has a spotter, LRF and PEQ2 mounted together on a tripod. After zeroing the PEQ2 laser to the center crosshair of the spotter temporarily (eventually the idea was to zero to infinity on the LRF reticle so night ranging would be possible without having to see through the LRF) I zeroed the illuminator to superimpose the laser, which wasn't so easy given the constraints. Anyway, what happened is the laser on high apparently magnified through the spotter and into the PVS14 leaving a decent size dark spot in the dead center with a clear crosshair in the center. Turning it off and turning it back on didn't fix this.

I figured it was fucked and was already figuring on getting a phosphor tube for the 14's and finding a decent NV optic or scope suitable to use the old tube in.

But when I got home and some hours later after all had completely cooled down, I tried it again and it was gone! All of it. No artifact, or dark spot, and with onboard IR and gain turned up or down I still saw no damage. So all seems well and that's good, I don't really have the funds to spare on upgrading NODs and buying another device at the moment.

So what happened? Did it overactivate some part of the tube? I figured a dark spot like that was a permanent fuck up. Never had it happen with 14's and lasers only (no spotter) so it's a new thing to me. Any insight into this would be appreciated. The PEQ has been removed, for now at least, but ideally I'd like to keep it due to the fact it's the part that allows for nighttime range finding, as well as marking targets while spotting.

 

[Killswitch Engage]

That’s normal. Any intensified light into the tube burns a temprorary image into the mcp. Lasers are very bad for it but plenty of dudes have burned an eotech reticle into their 14. As long as it’s not lengthy as in more than 15-20 min it’s not permanent. Much longer and you risk burning it into the tube for good. If it happens, putting it in a shoe box or absolute dark closet and leaving it on will generally repair it.

 

[McCrazy]

So what happened? Did it overactivate some part of the tube? I figured a dark spot like that was a permanent fuck up. Never had it happen with 14's and lasers only (no spotter) so it's a new thing to me. Any insight into this would be appreciated.

You probably did do a little damage to the tube but as long as it isn't obvious, it isn't a huge deal.

NVGs work similar to our eyes where if you shine a flashlight in your eyes while they are adjusted to darkness you will be seeing spots for a few minutes. NVGs do about the same but they have no way to self-repair any actual damage like our eyes have a limited ability to heal (like if you look at the sun or an arc welder).

Turning them on and off doesn't do anything as the chemicals in the tube need time to return to normal after being overworked, or however that voodoo happens.

 

[Terry Cross]

Would running a LIF on the front of the 14 add any insurance against sensor damage in situations like this? If the effect was from your laser, would the LIF help in the wavelength used on the PEQ2?

I know not to keep any NV stationary past 30 seconds or so when having any bright light or laser source in the view.

 

[The King]

The LIF would have helped yes. it may have even conclusively removed the issue.

My research on this is getting old, so any more versed laser experts please chime in.

That said, realize the peq is a dangerous unit power wise. Viewing the laser through a magnified optic can cause injury.

It’s about the light gathering capabilty of the optic - as it grows beyond what the human eye can accomplish it can move you back into the eye hazard zone.

Think about it like a pressure washer. It can injure you at the nozzle if the pressure is high and the flow rate is high. Laser wavelength and power are similar to these two concepts.

if you spray someone in the balls with the pressure washer from 1” away, they won’t be your friend anymore.

If you hit your buddy in the balls from 100 feet away he will probably laugh at you. And if some of the water splashes back on you, you will just get a little wet.

However, if you made some space warp machine (magnified optic) they brought your buddy 45 times closer, then again his nuts are being injured by the water spray. And you could get injured by the water bouncing off of the stump where his nuts used to be.

Eyesafe lasers utilize a series of techniques to ensure this isn’t a problem - one is a wavelength that is absorbed entirely by the outer layers of the eye instead of being focused onto the cornea.

Another technique is to fire the laser for such a short time that only a trickle of energy comes out.

And finally you reduce the power to a level where it’s impossible to sustain injury even if you held the thing to your eye all year.

 

[TheGerman]

Stop using the full power laser at close range; all it does when using an optic is bloom all over the place, make you see every spec of dust flying around and basically makes you lose your natural nightvision. If you can't see the low power laser at 100 yards, you're fucking blind. There's a reason there's a blue widget in the PEQ settings switch.

High power is primarily used at distance and the only time I've used it while on a gun with an optic was to designate something I saw/was on to someone else, to differentiate my laser designation from someone elses' or in a weird light at night situation that washed out the regular power laser; but these are all temporary pulses of the laser.

The dot/streak should go away on its own or if left running in its bag overnight. I've gotten them from looking at lights too long when tracking vehicles or some kind of light source I had to keep looking at for some reason.

 

[Strykervet]

Thanks, yeah, I've used these for twenty years but it's the first time using 'em behind a spotter and it's just the first time I've seen that happen. I'm not so much using it at that range as toying with it and it wasn't on high that long at all but it was sitting in one place. It's the first time I had it out and of course nothing was going right and I couldn't do anything without someone asking questions while I'm trying to do shit. When I finally do get a moment that's about all I had left. I just wanted to get it done and go home at that point.

A filter may be a solution, I haven't looked into it but I'm not sure if it'll work with the LRF and how it'll do placed between the scope and the 14. The LRF is Class 4, doesn't show up on NODs and has it's own laser filter built in and fires in pulses, so it's serious shit. I don't wanna fuck up the NODs, don't wanna go blind either. I'm actually more worried about what the LRF can do now, given this is a problem. I have glasses for the PEQ's but not the LRF, it's a higher wavelength and a much higher output (it's actually a cutting laser with a "low" output of around .5 to 1 watt).

I guess I have some research and asking around to do before I can confidently use everything together safely. At least no damage was done and it cleared right up after being off for a bit. I was just curious about it, never seen it before. I'm pretty good about taking care of my stuff but using them on a stationary unit vs. the head requires a bit more care apparently.