I thought it was 20hrs...  

Joking, though I remember someone saying that earlier this year.

Maybe a history lesson on early filmless systems and their original life expectancy and the improvements after should be written up and stickied?

Unreal that this is still going on

The vendor(s) spreading this horse shit should be ashamed of themselves and IMO this kind of crap should make people seriously question their credibility.

Holy shit, it’s a vendor saying this?

At one point earlier this year, people were saying that a certain vendor was telling them that info. And asking about it on this board. Somebody even posted screenshots of a text or PM that showed them saying it.

I don't 100% remember who the vendor was, though I'm pretty sure I remember. But i won't say for the sake of accuracy.  And someone who was actually told this rumor by them can say it they want to.

It is truly unbelievable that this rumor still exists. When the concept was in the R&D stage many years ago this was true, but the unfilmed tech of today shares very little with the original tech and is every bit as reliable/long lasting

ADONBILIVIT.

Vic, you’re gonna have to send me that scope to convince me.

In a society in which a presidential election can be stolen, misinformation is everywhere.  Name & shame w/ links.

So I can tube swap a pvs27 to an L3 filmless tube and not worry about recoil damage?

Good question. Because the guy actually doing those swaps seems to disagree. ¯\_(ツ)_/¯

I saw that. If Vic says he personally has a filmless clipon that he runs on a magnum rifle, then I don't see a reason to worry about it. Unless the sureshot guy has a recoil-damaged tube he wants to post some pics of?

I don't even have NV yet and I knew it would be USNV involved when reading the OP

Thats weird. Someone told me that it was impossible.

Yes, absolutely. I just know there were comments made about certain specs having a negative effect on applications with recoil. Wasn’t sure if people here were disagreeing with that sentiment or what. Obviously not on the subject of reduced performance after a certain number of hours, just on the clip-on topic. Here’s the quote I was thinking of:

The lower the halo reading the more susceptible the tube is to recoil damage. Or any vibration damage for that matter really, even dropping it while it’s powered on. The ITT and L3 “WG” (weapon grade) tubes that I’ve seen are all higher halo tubes as well. Most of those being around 1.0-1.2 to be exact. The tube that came out of this 27 is a F9815 wg. I’m going to do a little estimate on the halo compared to other tubes when I get a chance. I have a couple Elbits with 1.0-1.1’s to test it beside. But yes, a .6 halo tube would make me nervous in a 27 for sure.

https://www.snipershide.com/shooting/threads/what-tube-would-you-want-in-your-clip-on.7014678/#post-8695585

Who told you that? As long as the halos are above a certain level, the recoil issues diminish significantly. And immaterial to halos, filmless tubes are inherently less susceptible to recoil/shock damage because there is no film to become dislodge and create arcs

I did not say that all filmless tubes were unacceptable for use on clip-ons, did I? Just here on a tech forum hoping to understand the technical reasons for different claims that people make. A user brought up the issue, and I posted a quote and link to where someone had discussed the halo issue.

EDIT - do you know the technical reason why low-halo tubes are an issue? Also, do L3H UF tubes really have zero film as you said?

@jwramp


As I understand it (based on my recall of @TNVC_Sam videos on you tube, search silent solutions) Halo (in a filmed tube) has to do with the distance between the film and the micro channel plate. The greater the distance the higher the halo. So it stands to reason that with a higher halo (within reason) on a filmed tube the less chance of the film hitting the MCP and becoming damaged. Sam can correct me if I’m wrong.

TNVC, why don't you go over the history and cover the early models/releases.  That would be the open and honest thing to do.

Not surprised it's coming from USNV..... They just got caught trying to strong arm a small business and put on blast about it.  

https://www.ar15.com/forums/general/U-S-night-vision-tries-to-strong-arm-small-business/5-2396225/

Neither of those two companies were on my radar to buy from, and thankfully they never will be now. It’s well documented that early filmless tech had teething issues, but that was a very long time ago now. Apparently not for these clowns

That same guy also claims that the tubes aren't salvageable when removed from a 27.  He's definitely wrong about that.  

Well I guess I gotta apologize for not including the quote and context in my first response - didn't expect it to set folks off. Was out in the woods NOT finding any shootable bucks on opening weekend... The reason I responded to the earlier poster was because of information others had posted regarding caution needing to be taken when selecting a tube for clip-on swaps. I was not intending to insinuate that all filmless tubes have issues when putting them in 27s. Poster said "and not worry about recoil damage" and I was hoping to caution that there was more to consider than just "L3H UF tubes are G2G, no prob" which seemed to be what they were reading from Vic's comments in the OP.

As a filmless owner myself, I'm certainly interested in any technical information regarding the tubes and special cautions that may need to be taken as related to recoil damage. Obviously swapping tubes in clip-ons is outside of the manufacturer's warranty constraints, but if folks like Sam are agreeing that low-halo tubes should be avoided for clip-ons (am I recalling a comment in this thread that was deleted? can't seem to find it now) it just makes me interested in what the extent of that fragility is. I'm assuming the issue is with ANY tube technology in a clip-on with a low halo, and maybe the newer L3H UFs are just the first ones to regularly achieve those values. But if there's something in particular about the L3H tubes, it seems like a relevant discussion to have. I certainly don't have the experience with seeing thousands of tube spec sheets go across my desk - are those sub-0.8 halos common in older non-UF tubes as well? The 15 sheets I have in front of me from my and friends tubes range from 0.64 to 0.88 with the vast majority sitting right at 0.7.

Probably a rabbit-hole that is unnecessary to go down without actual test data to prove things, but when folks bring up a concern that could deadline a high-spec (high-$$) tube if used in the wrong application, it makes me perk up my ears. I only use these devices professionally in a photographic capacity, but local folks often have questions about the tech. When one seller is saying magnum rifles are G2G at 0.8 and another is expressing concern with smaller calibers pretty near that same value, I just hoped to get some technical clarification. My first response in the thread was not helpful in furthering that discussion - I apologize.


On the subject of how tube specs stay the same or degrade over their service life, I'd looove to see more on that. There's test sets out there where you can toss your tubes on them and print a new spec sheet, right? Would be cool to look at some of those high-hour tubes that you said your trainers are using to compare their current specs to what the factory published. Don't think Chip would let you crack open his 31s though...

IIRC, at some point in this video Sam touches how HALO and recoil sensitivity interact.

There do exist test sets that can *sort of* do that. However, generally the actual specs are based on what the inspector is able to measure using their eyes and the instruments on the test set. Resolution is still measured using a 1951 AF target.

Halos are measured by projecting a pinprick of light into the tube and measuring the size of the halo on a specially calibrated reticle. Different users may discern variations in the perceived halo, which is due to differences in their eye sight and also their level of experience and discernment.

SNR would generally be the spec that could decrease over time, but you could still measure a tube on two different test sets and get slightly different results based on the calibration of individual test sets. I'm not sure what L3 or Elbit use to test their tubes at the factory but I imagine they used some pretty special purpose equipment that's able to test the tubes without them being assembled into a goggle since they are measuring large quantities in a process/assembly line fashion. Whereas the best equipment that field technicians would use would be an ANV-126A or a NV-2500 test set, or similar. Both of which require a built goggle. You couldn't use a TS-3895A because it's an analog go/no-go test and only tells you whether a tube is within acceptable limits.

Count me in as someone who would love to see that data, from anyone.

Good stuff. Not to doubt the eyes of the staff at TNVC, but it just seemed like a more reliable path to pursue if trying to put whatever rumors there are over diminishing performance to bed.

As a selfish consumer of L3H tubes I'm also hoping their engineers are being completely honest about this. It'd just be neat to see the data to back it up.

IMO, like anything else, it is the responsibility of the accusers to back up their claims/accusations with scientific evidence gathered from legitimate methods.

Problem is, how would any of us trust that any 3rd party used was truly independent, etc.!? Let's face it, our crowd undeniably questions authority more than most.  

The main problem I have with this bullshit when it comes up is this:

Why do the guys who choose not to believe L3H (the manufacturer) choose to believe what USNV, NVD, or anyone else who are primarily thin filmed resellers have to say instead? And the EOTech argument doesn't hold water because they are completely different operations from each other.

Or then again, maybe it's better for "x" percentage to not buy unfilmed so it will free up tubes for the rest of us

ETA: And not trusting the 3rd party would go both ways. It doesn't matter what they found, whether unfilmed doesn't degrade or does within 500 hours, you'd hear "bullshit!" regardless.

Can I make at least one jab at @TNVC_Sam before you sticky this?

Funny, I thought this thread got deleted until I saw it up top

I remember the thread and appreciate all of the participants’ dialogue.

A tube that is already epoxied into the proprietary tube retainer for a pvs-27 can definitely be re used in another 27 that has a bad tube and simply needs a replacement.

If said tube is damaged upon removal of the retainer it’s worthless to me. I’m not spending the time or money to get a 10+ year old ITT tube re potted so I’m throwing it into the junk drawer and it’s a total loss.

Now with this being said, if you can guarantee that you can get them out of the retainer in perfect condition I will gladly pay you for each one you can do for me.

PM me if you can do it please.

Thanks
Jay

Good to see ya on here. Hope you can stick around.

Same, Jay’s a good guy and he knows his stuff. The NV he builds is high quality.

PM sent