Re: D760 Questions
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ASM1</div><div class="ubbcode-body">
From what you said,I assume the D740/760 must be better than a Raptor? Why would a raptor be heavier? it must use old tech with metal and O rings and such, if it used the better more modern light weight materials that the D740/760 use it would be as light and durable as a D740/760 from what you said the Russians must be better than American government engineering..?
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<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ASM1</div><div class="ubbcode-body">PVS4 is better than them all with a gen3 tube, Realy ?
D series You know what material the mecahnical assy are built from ?
D series You know what material the shims and gaskets are built from?
D series You know the reticule workings is a better design than the raptor ?
Realy not looking for guessing here,If you know spill the beans...keep it to facts if you please...
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Hi Asm1.
Firstly, you really need to learn to quote for effect. It's actually really difficult to read your posts. See above for a good example.
OK, you've asked me some questions, so I will respond.
Do I know the D-series mechanical/shims/gaskets/reticle? Nope. I only know what's shown in the pictures on the site quoted earlier and I said as much. From the pictures I saw, it looks pretty good that I did qualify that opinion quite accurately when I offered it.
As for modern engineering plastics, you'll find they often replace Steel and Aluminium with materials like Delrin. For small gears like you might find in a scope, these newer materials are probably superior and offer better life under normal use.
No where did I say the D740/760 was better than the Raptor. By all accounts, i hear the Raptor is a fantastic scope and is highly respected. It's designed to have a long service life and withstand being constantly punished. Why make it stronger? Because if, say, you happen to drop your rifle on a rock, scope down, you really want it to still be operating when you pick it up.
So if you think you might be working in dangerous environments where such things as bombs going off around you are a problem, then maybe the Raptor is for you. If you just need accurate shot placement and you take care of you kit, then maybe you don't need to spend the extra money and as an added bonus, you might save a little weight too.
Now. About the Russians.
Do you honestly think *anything* made for the Russian Military is going to be made lighter than the US equivalent? Russians are NOTORIOUS for over-engineering anything... So when they make something lightweight, even if it's for the consumer market, you know there's some real finesse involved.
As for engineering? Russians have been using paper shim for YEARS for optical purposes. It is, in fact, ideal for the purpose. eg,
http://jay.fedka.com/index_files/Page433.htm - I used to work with Romanians once and they taught me all kinds of things... There's a different mentality with eastern engineering. They see engineering materials for what they are, not for how people perceive them.
But if you DO know the exact answers to your questions, please post them...
As for the PVS-4? Dino's correct. A PVS-4 with a suitable Gen3+1 tube will outperform ANY current Gen3 scope.
Why? Even if it doesn't have the resolution, a Gen3+1 can have gain levels up to 300,000 times. Three times that the US tubes can currently make.
But even that aside, the main reason for the PVS-4 design's performance ability, even when you ignore the HUGE lenses and solid, proven military design, comes down to one factor. <span style="text-decoration: underline"><span style="font-style: italic"><span style="font-weight: bold">Chromatic Aberration</span></span></span>
The PVS-4 Cat lens focuses ALL wavelengths of light at the same location, while a Raptor focuses them at DIFFERENT locations. ( So does a D740/760 BTW ). This means that a PVS-4 type setup can maintain a perfect focus of an object across the entire spectrum to which it is sensitive. The Raptor can't.
So yeah, based on that one factor alone, I would say that the PVS-4 catadioptric type lens is better than ALL of the refractive designs... <span style="font-style: italic">Especially</span> for NV purposes.
But before you go getting all apochromatic in your response, read this...
http://en.wikipedia.org/wiki/Catadioptric_system
Just some basic lens science.
This is why people with Raptors and D740/D760's sometimes notice that a scope perfectly focussed for moonlight is suddenly out of focus with extra IR above 900nm.
But since in a Starlight situation, you really WANT the light above and below 800nm, it's a far more serious issue.
And I think we're about to see a renaissance of the Cat lens system in NV.
Regards
David