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Friday Night Lights: Dual Tube Spotlight

For Friday Night Lights I want to start a new ongoing series called Dual Tube Spotlight where we take a look at specific dual tube night vision goggles. I have already gone into some detail about various monocular devices and have spotlighted some interesting dual tube goggles like the PVS-21s. There are a number of dual tube designs even the Chinese BNVD-1431 but now we will spotlight these binocular NVGs and give them the attention they deserve. This week we will take a close look at the AN/PVS-15.

USSOCOM Used AN/PVS-15

For some, the PVS-15 bino NVGs are on a pedestal for the mere fact that it was adopted by USSOCOM.  US Army Rangers in the photo above are using PVS-15s in the GWOT. They were designed and built by Litton Industries before they became L3 Technologies. But how are they as dual tube night vision goggles?

Two Is Better Than One

Just like shooting a red dot on a firearm, using both eyes is better than using one eye. The same goes for night vision. No, biocular devices like the Lucie/O-NYX or PVS-7 do not count. Our vision has evolved into a complex system. So adapting them for night time use, we should take advantage of our natural binocular vision. We perceive the world using two eyes. Each eye takes in a slightly different image than the other eye and our brain stitches these two images together seamlessly. While you can use a monocular like the venerable PVS-14, it is not giving your brain all the information it can get. So the next best thing? Dual tube NVGs.

Take a look at the PVS-15 housing. It is sort of like a set of binoculars. The monocular pods are articulated on a hinge attached to the bridge. They are not fully articulated like the PVS-31 or the DTNVGs. The articulation is Litton’s answer to interpupillary distance adjustment. Each person has a different measurement between their pupils. When even you try using a pair of binoculars you roll the monoculars in or out to fit your eyeballs. The same goes for the AN/PVS-15.

Here is the AN/PVS-15 stored up on the helmet. Articulated binos like the DTNVG or PVs-31 style can roll the monoculars past 90 degrees which shifts the weight of the NVGs closer to the helmet. Making it a lot more comfortable to wear for extended periods of time. That is not the case with the PVS-15s.

AN/PVS-15 stored up

AN/PVS-15 stored up with the monocular pods set for use.

AN/PVS-15 monocular pods folded up and stored against the helmet. Not much difference.

The PVs-15 bridge design seems big and bulky to me when compared to other binocular NVG designs. The bridge is excessively tall but I think that is due to the helmet designs that this goggle was built around. It was probably first implemented on a PASGT then the MICH and ACH helmets. Those helmets were not that ergonomic and so the mounts sat a little high on the helmet. Which means you need to physically lower the tubes so the soldiers can look through it. With modern helmet designs, this positions the goggles lower than I would like and you need a mount that can adjust the vertical height so you can bring the tubes high enough to see through.

Just look at the bridge up close. That is more than an inch of height that is not necessary. There is one cool feature that the AN/PVS-15 has that I have not seen in other dual tube NVGs. Litton’s refocus lens for the IR illuminator.

We saw a similar IR illuminator refocus lens on the Litton M942. Below are examples of the PVS-15 IR illuminator in use.

IR Illuminator OFF.

IR Illuminator ON (no refocus lens)

IR Illuminator ON with refocus lens in position.

At close range the refocus lens is not that useful. But slightly further out it is slightly more useful.

IR Illuminator OFF 40 ft.

IR Illuminator ON 40 ft, no refocus lens.

IR Illuminator ON 40 ft with refocus lens.

The IR illuminator is not very powerful. It was designed for close area illumination. However I have been told by my friend Aaron, the guy who had the PVS-21s, that he likes the tighter beam for spotting wild life at night. While the IR illuminator won’t illuminate an animal that well, it does help light up their eyes. Sort of like the trick I learned as a Boy Scout, where you hold a flashlight to side of your head parallel with your eye sight. Then scan the ground as you walk in the woods. You will see tiny little eyes looking back at you. Those are spiders looking at you. The PVS-15 illuminator refocus lens can help you do that. Is it useful? Depends on your case use. Maybe if you were hunting small game it might come in handy. But for any real practical IR illumination you are better off with a dedicated weapon light or laser.

PVS-15 Optics Are Different

For the majority of dual tube NVGs out on the market now, they all use PVS-14 style optics. I am talking about the objective lenses and eyepieces. However, the AN/PVS15 uses a completely different style of lenses.

Functionally the PVS-15 eyepieces operate similar to the PVS-14 eyepieces. They have built-in diopters. Rotate the knurled ring and the eyepiece translates forwards or backwards.

PVS-15 eyepiece all the way rearward.

PVS-15 eyepiece all the way forward

Because the eyepiece moves deep into the eyepiece housing, you are limited to what screw on accessories you can attach to the rear eyepiece. If you can find them, there are amber filters that can screw into the rear eyepiece but they must be flush fitting. Other accessories like the LPMR POV recorder has to have a proprietary housing made to attach to the eyecup retaining ring which you can see is part of the outer housing. Since the eyecup retaining ring does not translate with the eyepiece, you do not have to adjust the position of the PVS-15.

The objective lenses are somewhat similar to ANVS-6. When you adjust the focus with a PVS-14 style objective, the entire lens cell spins. But for ANVS-6 and AN/PVS-15 they just translate forward and back. No spinning.

PVS-15 objective all the way out.

PVS-15 objective all the way in.

I have been told by a number of people that the optics of the PVS-15 is superior to the PVS-14 optics. However, I have not found that to be true. They are not inferior to the PVS-14. I just do not find them to be better than the other. There is a lot to be said about what kind of image intensifier tubes are in the PVS-15 which may be a big reason why they appear to be so good. I have a set of tubes out of a PVS-15 and put them in a Sentinel housing. I did not notice a difference due to the optics. So when someone says the PVS-15 optics are better, it could be a personal preference. The problem is whether or not that person is comparing the same thing and eliminating variables. Intensifier tubes are very different from one another. So unless they used the same tubes and then compared the different lenses, I am skeptical about that analysis.

The AN/PVS-15 is powered by a single AA battery and runs for 10 hours continuously. Just like the PVS-18, the battery cap faces rearwards. This could make it possible to have a remote battery pack adapter that does not have to reach around to the front like other dual tube NVGs.

 

On either side of the bridge are lanyard tether holes. This allows you to tether the PVS-15 or use the bungee hooks found on modern helmets. By attaching the bungees to these anchor points you can minimize the PVS-15s from bouncing up and down.

Weight wise the PVS-15s are a bit on the heavy side. 23.1 oz or 656 g. Compare that to the PVS-31 which is 15.5 oz or the ultra-lightweight Photonis BNVD at just 350 grams.

Final Thoughts

The AN/PVS-15 is a solid night vision goggle and it served our military very well. However, its design is outdated and there are better dual-tube housing designs out there. The price of a PVS-15 has dropped a lot. You can get a beater pair for around $4,000. The low cost is a reflection of the tubes inside and not so much the housing. One problem with the PVS-15 is that there is little support for them. PVS-14 optics are rather plentiful, PVS-15 optics, on the other hand, are not that common. I do not find people selling them separately. So while the PVS-15 is cool for those who want to clone or LARP the GWOT, there are better options out there.

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