I would alter horta's specs slightly ... to try to keep the MSRP under $10k ...
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1 - the unit only has to be a clipon ... doesn't have to be a (good) monocular or a (good) thermal weapons scope ... though adding limited abilities in these two areas could be done with minimal additional cost (more on that later).
2 - I would ask for minimum objective lens diameter (the germanium part) of 60mm ... this is to ensure we get adequate "information" to the core, even in poor thermal conditions.
3 - Size and Weight I'm not so picky about ... I would be running a thermal clipon on a rifle off a tripod ... and even my "light" bolt guns are 15 lbs when fully decked out for the field ... these are the Bravo chassis guns. The AIAX chassis guns are around 20 lbs when fully decked out for the field. The UTC/x/xii size is perfect for me. Doesn't have to be cratos size in my book.
Where I would spend the most in terms of additional cost would be on the rear end.
Since this will be a clipon, the net magnification needs to be 1x (otherwise our reticles won't work very well for holding)
So three aspects needed on the backend to make a thermal clipon that beats the commercially available units.
4 - Collimation.
The military clipons I've had (or used) have all been "truly collimated" ... meaning, mount and shoot. If the optical center of your day scope is within the collimation tolerance of the clipon ... then your POI shift will be negligible. This is NOT the case for the commercial clipons. They have adjustments and require adjustments. The military clipons do not. The military clipons have rotating prism assembles, which create the collimation tolerance ... and I'd like to see this dream clipon add those prisms. I know some say this is not needed. But I am not yet convinced. I want "mount and shoot" (if within tolerance) ... and for me this is actually my #1 feature that I want for this dream thermal clipon !
5 - Day scope support for at least 8x.
While not needed for most night hunting activites, I still want at least 8x on a thermal clipon. I like to shoot steel out to 900yds day and night ... and the thermal clipon can do it with 9x on the day scope for 12 inch steel. So that's my #2 feature in terms of priority. So this requires the combination of the front and rear end lens assemblies to produce the right balance of front end magnification and rear end demagnification to support such day scope magnificaiton requirements. The trade off is FOV .. the FOV of such a "long distance thermal clipon" will be less than a clipon without this requirement. A long distance thermal clipon like the UTC/x/xii are under 7 degrees FOV ... the LWTS-LR might be 9 degrees IIRC. The short distance thermal clipons, which support day scope magnification up in the 4x-6x range ... would have about double this FOV and folks that are strickly using clipons for night hunting my prefer this FOV range. So I would allow two version of this dream clipon. But I'd be buying the LDTC version myself
6 - DIsplay
One key to making a long distance thermal clipon work, is the display, so we need a high res display back there. At least a 1024 if not a 1280.
So these three aspects ... the prisms, the balancing on the focal lengths ... and the display will be where a lot of the cost for this particular widget will be, but that's what I would prioritize.
7 - Integrated LRF/AB/Distrubed reticle.
Personally I can live without this ...I use external range finders and reference my internal DOPE card (in my brain) for shots out to 500yds. And have more time to consult kestrel for shots > 500yds. But I am not opposed to a more expensive (over $10k) version that adds these features. I'd just like a "bare bones" version with out them.
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What can we give up to get this ? Well believe it or not, I think we can give up 640. I'll need a second full length article to explain all the details ... but this is a way to save cost ... not just because the array is cheaper ... but because the lenses can be smaller ... THAT's where most of the savings can be. And if you want small ... this is what you want. The front end focal length to array size ratio is a key metric as is the number of pixels in the display. And 320, 336, 384 is viable in a clipon if these values can be optimized. And this can remove cost without degrading PID, that's the bottom line. I'm sure most people will disagree with this. But I need to help educate those folks as I myself had to get educated in this area. I'm working on a post which will explain further !!!
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How to add ability to use clipon as a TWS ?? Add an optional magnifier for the backend. To "zoom in" on the TV ... like a 3x screw on magnifier. I had one of these for my first Apollo. And I used it as a TWS more than I did as a clipon. So that might add a couple of hundred ... to the price, but it could be an accessory. What this magnifier does is back off" from the inherent optical demagnification on the backend lens. It does not change the FOV.
And of course, any thermal can be a handheld. Well any thermal we can buy. Just rig up a lanyard for it and wear it around your neck. But I don't want to compromise a good long distance thermal clipon by requiring it to be head mountable. That's a different widget in my book. There I do want to minimize size and weight. But I don't want that for a LDTC because I want to decent sized lens on the front to pull in that information!
