I got my nvision zone 3 blem pvs-14 in on friday last week, so I don't have much time on it at all, but since it feels kinda like someone put i2 inside of my $300 primary arms 1-6, and in no way whatsoever reminds me of my razor gen III, I figure I should check on some stuff with y'all.

First, how much image movement is normal for a pvs-14? For example if I hold it up in front of my face about the same place it sits on my helmet, and then move it around (up-down, side-to-side, or around in little circles) the image dances a bit and moves in the opposite direction that the monocular is. Also, though I can set the objective focus on infinity just fine, when I move back to the eyepiece I can't ever really settle anywhere and no matter where I put it I can't get rid of the distortion; using looking at my feet/the ground rite in front of me as a refference, I have to set it so that either that's fine and everything farther than 10-15yds out is all wonky (when I look around it feels like I'm turning my head faster than I actually am/ is noticably uncorfortable to view), or distance is fine but when I look at my feet it'll throw off my ballance a bit (not like a vertigo spinning kind of way, feels more like I'm falling forward even though I'm not, especially when I look straight down at my feet).

I know there's supposed to be a bit of off-ness from the loss of biocular disparity, and honestly this stuff isn't that bad if I'm just standing still and looking around, but as soon as I start moving I find I'm having to put noticable effort into mainatining my ballance/ sense of direction so this seems like something else; I can cover/close one eye and walk around way easier than with the mono (honestly neither walking or driving that way have ever bothered me), and though I suppose the effect feels in some ways similar it is seriously, seriously, seriously exagerated.

Hope y'all can offer some insight.

eta: forgot to add that when mounted it's on a g24->wilcox bridge->mod armory d14 dovetail arm, incase that matters.

sounds to me like you got some china or knock off glass.

there was a huge thread on here about it a little while back.

Well you aren't gonna see your feet in focus with an infinity focus set. Gotta pick one or the other.

Typically there isn't much distortion. It feels like you are looking through an open toilet paper tube

Did you happen to order or receive 50 degree FOV lenses instead of 40?

Rotate the objective lens all the way out and tell us what the numbers are.

@N-VisionOptics

By what you’re describing, it sounds like you’re referring to depth of field issues. When you focus at infinity, you can’t see things close up clearly. Conversely, when focused near, you can’t see things that are far away.

It's not a focus thing, I know that'll be out, and is regardless of adjustments I make, I'm talking about the image itself. When I set it so distance is fine then look down I'm getting some serious fish-bowling and magnification, prob around 2-3x.

Not getting a toilet paper tube feeling at all.


Will do later tonight, I'm away from the unit atm.

I know OP referenced the objective focus, what about ocular diopter (rear focus)?

That's the one that's giving me trouble.

https://www.ar15.com/forums/Armory/PVS14-Distortion/18-522307/

You are describing the exact issue that I saw in my friend's unit. His unit was from NVision as well.

Do different pvs14s have different depth of field? I feel like my TNVC unit has much broader depth of focus than my previous pvs14s have. All were high quality units, with my tnvc tube having specs in the mid range between them.

No. You can change how far you can rotate the assembly by adjusting the lock ring.

It's probably imagination, but I feel like my current 14 just has more depth than my others have. My others, if I was 15ft from my dog and he was facing me, his nose would be crisp, and his tail slightly off perfect. This one seems to grab the whole dog, so to speak, and it's far easier to see steps with it up close even when set to infiniti.

I’ve noticed similar phenomena. Like on some of my goggles, I can have them set at infinity and be able to see things clearly a few feet closer than other goggles with the same glass- exactly the same glass from the same lot even. Not sure why

Sample number is 3 in my case, 2 Carson, and 1 MNVD. UNV, L3, and TNVC. The TNVC seems to have more depth of focus. My diopter for it is set at around 0 to -0.5. My diopter for the L3 was around -0.4. My diopter for the UNV unit was -6 or something, as the setting was not true. If diopter matters. All tubes were l3 filmless ranging from 2200 fom to 2900fom, roughly.

Just as a data point, my n-vision zone 3 has none of the issues you are describing.   Certainly not magnification.  

Take a photo through the tube for us?


Anyways though, I would call up chris at n-vision and let them know.   I imagine they will check it out for you.

012021 80063-A3256364 1XEP3 383304


That's the plan for today. Here's some pictures, two of objective housing, one through the tube, if you look around the edge of the left side of the walkway at the bottom you can see a really good example of the fishbowling I'm talking about, it doesn't make you fall over till you start looking at your feet, but's always there; that plus a dancing image aren't exactly fun to look through.

Link to album with full size images if you want to see 'em

how'd y'all get it resolved?

That doesn’t look too out of the ordinary to me. That’s a mil spec Carson eyepiece you have on there. The edge distortion you are seeing is nowhere near what I’ve seen in some of the cheap Israeli glass. In fact, it may even be normal, check your data sheet to see what the edge resolution should be.

He has not sent it in yet. I've looked through lots of different tubes, and have never seen another one that looked that way under movement. If what NVision says is true that all components are milspec, then perhaps the intensifier itself is the problem?

“Problem” is a strong word. The photo you posted looks pretty typical, the edge distortion is something you’d see on any tube if it’s not aligned to your eye properly

ETA: here’s a pic through an ANVIS last night. Similar edge distortion from the camera angle.
Attached File

I can almost guarantee there is no issue with your actual components of your system based on the images. NVision builds things properly using good quality components.

The issue is either that your brain is simply not used to moving with monocular night vision and possibly having some issues properly focusing the device, OR a very slim possibility is that your system has a lot of optical divergence and needs to have the eyepiece adjusted to correct for it. It's the same process as collimation but since it's a monocular system I doubt highly most builders actually check for it, because there typically is not enough to cause any issues. I'm honestly not even sure if its possible to cause any serious issue.

Realistically it may be a combination of several of the above. Your brain is not used to movement with the mono, it may or may not be 100% properly focused, and it is also bending light enough to give you some issues with perception/distortion.

I can't speak for the other guy, but I have a lottttt of hours under a pvs14. My friends and I all passed it around and agreed that it is the unit and not just improper use.

Should there be no image movement at all during the jiggle test?

I'd definitely like it if there wasn't anything off, it just doesn't seem like it. The thing about that stuff around the edge is it doesn't ever stop, it just gets so slight that you can't see it till you start looking around. I went outside to check again last night, and looking at that house in the photo, while focusing on one point, say the corner of a window, as you look left to right taking that point from one edge of the picture to the other, you see it roll as it crosses the center of the picture and it shifts to whatever side of the image it's headed towards as it does so; it's like it's traveling across a very slight bubble. If I throw the diopter setting way off it exaggerates it, but even adjusted down to be as minimal as possible it's still there, and if I do said adjusting while looking at an object say 10yds or so away, when I look back down at my feet it gets dialed up again and vise versa for adjustments made on objects closer up, though admittedly not as bad when done in that manner. When viewing through the tube as a handheld, and shifting the whole thing up and down left to right and around in little circles in front of your eye, you can really watch the image dance, it's pretty disorienting.

There's actually a member here with oodles of NV stuff who happens to live in the same city as me, I'm going to try to get ahold of him this weekend and have him look through it to see what he says before I get ahold of n-vision, hopefully I'll be able to find out  if it's a just me thing or not, this sounds just like what @13willak encountered with his buddies tube though so I feel pretty confident that it won't be.

What ever happened with this, the unit was fine, correct?

No there's something wrong with it, everyone I've gotten to look through it says the same thing, it's like you're viewing through a prism or something. I just haven't had the chance to get with that local guy who has a bunch of NV stuff to have him check it out, which I'd like to do as a final check before sending it in. Happened to get real busy the day after last post though so I haven't had the chance yet.

There is one thing you can check. Take the eye piece off and then remove the tube retaining ring and light pipe. pull the tube out a little and slightly rotate the tube back and forth ten reseat the tube making sure it engages the alignment pin on the front of the housing. It could be in crooked and that's what's causing the distortion.