Night Vision EOTECH CLIP ON THERMALS ( Full details)

I had already talked myself into an Xelr, then I talked to Preston yesterday and now I 'm sold. I'm still kind of a poors so don't tell my wife... She knows where I sleep at night. Now I'm waiting for more videos.
I'm still working on talking and saving for one. It takes me a while to save up that much with how I am currently spending my paychecks.
 
I just swapped an old IOR 3-18 (long overdue) for a Revic 428 smart scope. 4.5x on the low end is higher than I'd like for night shooting, but the ballistic solver in the scope is awesome with a SiCo Radius and a clip on. I'm getting a better image at higher magnification with the Revic too.
A Steiner 2.9-20 IFS may have been a better choice but then I wouldn't have been able to order the xELR.
 
I just swapped an old IOR 3-18 (long overdue) for a Revic 428 smart scope. 4.5x on the low end is higher than I'd like for night shooting, but the ballistic solver in the scope is awesome with a SiCo Radius and a clip on. I'm getting a better image at higher magnification with the Revic too.
A Steiner 2.9-20 IFS may have been a better choice but then I wouldn't have been able to order the xELR.
You wreak from the stench of poor.
 
You wreak from the stench of poor.
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You’re definitely heading in the right direction here. I hope my encouraging words played some small part in your new life course.
Anyway, kids are born with extra kidneys, right? Asking for a friend.
This is why Horta travels to Africa so often. All these toys get expensive for a stay at home dad
 
I may have missed this in an earlier comment, but is the xELR collimated with a prism or does it have to be self adjusted for every platform it mounts to?
Per my recent readings in the last 2 or 3 months here on SH, it appears (if my comprehension is correct) that thermal clip ons do not contain a risley prism like some of the NV clip-ons.

I think that even "some" of the higher end thermal clip ons have a "user ability" to adjust the screen to fine tune POA/POI with the day optic.

However, hopefully some of the more knowledgeable people in that arena will come along and shed more light on the subject.
 
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Military thermal clip ons (at least almost all of them) have no user adjustability to make them work with the day scope. This is because they leave the factory already engineered to work with day scopes without significant affect on day scope POI.

There is some debate/discussion about HOW military thermal clip-ons accomplish this. Is it a prism? Is it ocular lense design? Is it software/pixel arrangement at the factory? Is it some other magic?

Industry insiders have given conflicting statements about how it’s accomplished, and it may be accomplished in different ways for different devices.

What IS certain, is that all military clip ons (with one possible exception) are designed/intended to mount, dismount, mount to a different weapon, etc., with no adjustment needed (and usually no adjustment possible).

So far, commercial clip-ons have failed to figure out the magic and have relied on zeroing the screens which is vastly inferior for several important reasons.

Reports on the Theon units (and the fact that it’s been adopted by a serious military) tell us that whatever specific method/magic was employed, no adjustment are necessary to mount-shoot-switch weapons, etc.
 
So far, commercial clip-ons have failed to figure out the magic and have relied on zeroing the screens which is vastly inferior for several important reasons.
Can you expand on the reasons shifting the screen around to zero is vastly inferior.

I understand and recognize that you do not have the convenience of going from rifle to rifle without having to make adjustments, but are there other reasons that the commercial solution of shifting the screen is vastly inferior.
 
Can you expand on the reasons shifting the screen around to zero is vastly inferior.

I understand and recognize that you do not have the convenience of going from rifle to rifle without having to make adjustments, but are there other reasons that the commercial solution of shifting the screen is vastly inferior.
From my little experience with the Yoter-C you're basically adding a second aiming device with the screen shifters. If it moves or deflects or the mount shifts, so does your POI.

Example. Lock the rifle down in a vice and aim the optic at a 100yd target. Now add your thermal to your rail. Since it isn't aimed precisely at the target, you shift the screen around until your cross hair is back on the target in the image to compensate. Now if you deflect the forend as if you loaded the bipod or the mount moves or doesn't RTZ, the thermal is "looking" somewhere else and the image on the screen moves again to reflect where it's looking now. The action/barrel/day scope didn't move, but your target isn't under your cross hairs anymore.

If someone can explain how the "coliminated" military optics seemingly pass the image straight through the scope without affecting the POI or requiring any adjustment, I'm very interested in trying to understand it. Or at least point out the flaw in my thinking.
 
Like a lot of people here I started seriously looking at buying thermal clip-ons in the last couple of years, and at the start, I heard a lot about how the best systems were collimated with a Risley prism. My current understanding is that that is largely accidental misinformation carried over from the world of night vision (image intensification) clip-ons. I will explain my current understanding below, but I am happy to be corrected by an expert if one comes along.

A Risley prism is basically a clever arrangement of wedge-shaped prism lenses that allow you to "steer" a light beam or path. See here for a neat demo with a laser beam: YouTube link. Although the laser beam comes out of the emitter in a straight line, you can see that you can alter its path very precisely by rotating the prisms to a certain position. Some high-end NV clip-ons like the PVS-30 use such a system. It is not user-adustable, but during the manufacturing process, each device is attached to a test fixture and aimed at a calibrated light source, and then the prisms are set such that the image seen at the ocular end is the same as what goes into the objective end. Then the setting is locked down, and the result is that the image is basically passing straight through the intensification clip-on without being distorted or bent. Thus, as long as the day optic and NV clip-on are reasonably aligned, there will be minimal POI shift when the clip-on device is attached.

Thermals are different. The light is not really "passing through" the device in the way that light passes through an NV tube. The infrared waves fall onto a microbolometer sensor (or a fancy pixel-counting sensor for cooled MWIR systems) and are stopped completely there. For the clip-on to function correctly, you really just have to ensure that the displayed image on the rear screen matches what the day optic would have seen when the clip-on is removed, but this does not require any "bending" of the light path at all, so no Risley prism is necessary. Instead, special software calibration systems are used to ensure that a given pixel on the microbolometer activates the correct pixel on the display screen on the back of the unit when it is hit by infrared light. They also have to ensure that the image size is calibrated correctly, so that 1 mil on the day optic reticle is 1 mil when looking through the clip-on, and not 1.002 mil. This is factory set for military clip-ons primarily to ensure the device will work with minimal POI shift on just about any weapon if the day scope and clip-on are reasonably aligned. However, there is no real reason that a civilian end-user couldn't fine tune the screen image position for their exact rifle, and indeed, many thermal clip-ons allow this. However, doing so ruins the ability to slap the thing onto any rifle in your squad and have it work well enough to engage the enemy without re-calibration. Since the military doesn't want to futz with calibration, the extra cost of pre-calibrated units makes sense, but for civilians, that extra labor isn't necessarily worth the extra price tag, so it can be omitted on civilian units. The owner is then forced to calibrate the clip-on for a given rifle or a few rifles in his collection. Many clip-ons intended for military use do not allow the owner to even access a calibration menu, to prevent grunts from fucking up the calibration.
 
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Regarding the advantages of military clip ons vs screen aligned clip ons, Ksracer hit the nail on the head.

Civilian thermals:

1. Cannot be reliably moved gun to gun to gun. (Some can by selecting different zero profiles, which is better than nothing)

2. Rail/chassis flex results in a miss (ALL rails and chassis flex)

3. Return to zero mounts… don’t.

4. Theoretical (perfect) RTZ mounts still don’t work if dirt, grit, lint, etc. get in the mounting surface of the mount or the gun.

I’ll admit that practical results for most pig/yote hunters using commercial clip ons are often better than the above list could make it seem. If your interests don’t include real world life or death situations, commercial clip ons may be a very viable option.
 
Lol I dont know anything about vudooo or magic. I know there is most likely specialized equipment that goes into building these things.. which most likely is why commercial devices cost 1/3 of the Mil devices prices …
Or... they're less expensive due to differences in materials, build quality, component prices, R&D, and brand reputation.... you know, like most things.

Not sure how much of that cost is the magic...seems to vary. ;)
 
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