A Rundown of Common Night Vision Binocular Features - What You Need vs. What You May Not

In a continued effort to make night vision device selection less confusing for the average buyer who hasn't been able to use a lot of different systems, this article is meant to identify and describe common features found in modern night vision binoculars from the perspective of an advanced end user. We've done our best here to try to relate in real world, no-nonsense terms what features the average night vision user might actually value in various common use cases. Keep in mind, there's almost no 'bad' night vision device features, but typically every feature comes with some kind of additional monetary cost or availability tradeoff in the bigger picture, so the question becomes not whether or not you should avoid certain features, but rather which is the best device that meets your real needs and budget. 

As always, before we go further, we are going to include the disclaimer that this post was not written by AI, and it has been produced by real night vision experts with thousands of hours of experience in use of night vision technology.

Macro NVD Features - Articulating pods, Panning pods, or Fixed pods

Before we get into the micro-features, first we need to cover a couple macro-features that both provide some kind of feature or benefit, but also are structural design elements of an NVD and help categorize systems into common types. 

Outside of a couple exceptions, binocular night vision devices (commonly known as BNVDs) generally fall into three designs related to how their optical pods -or the parts you look through -behave. 

The most common device today is an articulating device, which is defined by hinge joints on either end of its bridge which connect the pods to the central bridge. These joints allow the pods to rotate on an axis, which enables the user to be able to push a single, or both, pods up out of their direct line of sight around or above eyebrow level, so that they can easily use their natural vision unobstructed, but without having to use their night vision mount and stowing the whole binocular up onto the top of the helmet. 

In terms of commonality, a distant second design of binocular is a fixed bridge, which just means the optic pods that you look through are attached directly to a single piece central bridge. Fixed bridge goggles allow you to slide the optic pods left and right to match your interpupillary distance, but otherwise the pods are fixed in place (and can't rotate upwards out of sight independently). 

And finally, a more recent design has come to the commercial night vision world that allows pods on the night vision bridge to pan, or angle outwards, allowing for an increased field of view without the use of special lenses. Most importantly, this feature is not mutually exclusive from the other two primary designs, meaning a goggle can be both articulating and panning, or fixed bridge and panning. 

At this point, it probably makes sense to line out the hierarchy of features and factors that might result in you wanting to choose one housing type over another. At the top of the hierarchy is the macro design or style of binocular outlined above. Panning is not a mutually exclusive design choice, as there are articulating/panning goggles, as well as fixed bridge/panning goggles, but there isn't really such a thing as a panning goggle all on its own. This is why we consider the material of the system as the second tier of the hierarchy, as this will also heavily influence both the weight and the impact strength of the system.

 

Micro NVD Features

The finer features of a BNVD are often what become the focus of most buyers' deliberations when selecting a system, for better or worse. Even though we list them as 'micro' features, that doesn't necessarily suggest that all of them are inconsequential and purely preferential. Here we briefly describe the most important and common micro NVD features, with our take on how significant or not each of these might be to a particular type of night vision user. 

External power (battery pack)

The availability of an external power source, generally a battery pack worn on the back of the helmet, came about as a means for pilots to be able to fly longer missions using night vision. The same concept became adapted to ground systems for the same reason. Other benefits include redundancy of power in the case of a critical outage of an onboard battery -basically an insurance plan against your battery failing at the worst possible time. Power packs also are often viewed as a 'functional counterweight' or a source of necessary balance weight on the back of the helmet that provides you with some kind of additional benefit rather than just being dead weight. 

The biggest benefit of an external power source that is often overlooked is the potential to allow a different battery source to power your goggle than the one that is onboard. Some battery packs on the market allow mixed battery types and then properly regulate voltage as necessary depending on the selection.

External power is not a 'must have' for almost any user type aside from the highest levels, but it can be nice to have. However, packs themselves often add a few hundred dollars of cost increase. 

Interpupillary stops (IPD stops)

IPD stops are physical stops located on either the bridge or the pods of an articulating system, which are meant to stop the travel of the pods at a specific point aligning with the interpupillary distance of the user. This way, on an articulating goggle where the pods can be rotated upwards off axis, the idea is that they can be rapidly returned to the down position and stop at the same exact point every time. 

IPD stops are good in theory, but often in the real world fairly useless. This is because, for the feature to actually work as intended, the end users helmet position has to NEVER ever shift, even just a millimeter or two. We have found this is not realistic and therefore put almost no weight on whether or not a system has IPD stops or not.

Onboard infrared illuminator

An onboard infrared illuminator provides some output light directly from an emitter on the bridge of the system, so that the user of the system can always have some form of non-visible light for the intensifiers to amplify and therefore provide a quality image, even when the natural conditions are extremely dark. 

An onboard illuminator can definitely come in handy for certain users and applications. For users where extra equipment is very limited, and other sources of illumination aren't practical or available, an onboard IR illuminator can be a life saver. Famously, the current SOCOM issue goggle does not have onboard IR, which leads some to assume it must not be that important. 

While we disagree and think it can be a very good feature to have, the reality is that you can always have infrared light emitting equipment on your person, but not on your goggle, and have the same capabilities. This makes it not a must have, but a nice to have feature. 

Manual gain control

Manual gain control, as opposed to automatic gain control, allows the user of the device to adjust the gain of the system on command. This is contrasted against a goggle that only offers automatic gain control, where the intensifiers will run at maximum gain as a default at all times. Lowering the gain of the system reduces the output brightness to your eyes, and also can reduce excess noise in the image if you're around more light than is needed. Reducing output brightness of your intensifiers is very beneficial for situational awareness when there is moderate levels of ambient light, because the intensity of the brightness of the night vision won't artificially keep you from not being able to see in your peripheral vision "outside" of your optic pods. 

In the past, manual gain control meant some kind of trade-off -mainly a lot of extra cost or limited system choice. The feature is useful for numerous reasons, but in the past may not have outweighed cost and limited availability tradeoffs. Today, however, manual gain control is becoming ubiquitous and also cost competitive, giving users little reason to not have it's benefits. Even still, there are some lower cost quality binocular systems that don't offer manual gain control, and we still don't think there's a reason to pass up a great auto-gain system just because you can't have manual gain control (either for cost or other reasons).

Adjustable pod tension

Another micro feature only available to articulating goggles, this feature will allow the user to adjust the amount of force needed to rotate the optic pods up or down. 

This feature is vastly overlooked, and offered in most, but not all, articulating goggles. Although most new users assume that optic pods should require lots of force to move as to avoid them shifting during violent movement or minor impacts, we have found that the opposite is actually true. Pods should be set to just enough tension to keep them in place when you sprint, but light enough you can effectively move them up and down with one hand without transferring any force into your helmet, causing your whole helmet to shift.

Although it's not that common, an articulating goggle that does not provide adjustable tension often will have pods that are very high tension and therefore difficult to move. This puts end users focused on performance shooting or high risk operations at a disadvantage, and should be avoided at all costs. 

Infinite focus stop

An infinite focus stop ring will allow the focal distance of the binocular to be physically stopped at a given point, usually at or just past the distance where the end user can see things from a given point into infinity in perfect focus. This is sort of the 'default' focal distance setting for night vision operations, but many users might find themselves adjusting the focal distance of the goggle closer than the infinite default to do things like read writing or signs, do fine motorskill tasks on equipment, render aid, adjust equipment in their immediate vicinity, and so on. 

The value of an infinite focus stop is that the end user can quickly go back to the 'default' focal distance just by turning the objective lenses until they hit the stop. This is preferential for most rather than actually having to make many fine adjustments to achieve infinite focus -or worse, have lenses travel well beyond the point of infinite focus into a zone where nothing is in focus at any distance. In this scenario, newer users often can find themselves fumbling in the dark to try to be able to see anything. 

Infinite focus stops are common, but not on every system. Still, they're common enough for us to not really need to make a huge deal about them, because it's generally not going to be a decision factor. Only the PVS-31A, 1531, and NVD-BNVD SG series today do not feature an infinite focus stop.

Automatic power shutoff

This feature is mostly associated with articulating goggles, but can also be found in a slightly different fashion in fixed bridge goggles too. A goggle with this feature will automatically cut power to one or both tubes when a certain action by the end user is taken, such as rotating an articulating pod past a certain degree of its travel. In a fixed bridge system where pods don't rotate, the power can be cut to both tubes when the goggle detects it has been stowed on its mount on top of the users helmet. In some cases, an articulating goggle can have both of these kinds of shutoff, giving it the most adaptability. 

Automatic power shutoff is a very useful tool for every user of night vision, and therefore it makes it difficult to recommend a user choose a system without this feature. A few fixed bridge goggles don't offer this feature but are otherwise quality goggles, but these are usually lower cost options where features are stripped out to reduce cost. At the end of the day, automatic shutoff doesn't really affect the human performance of a user in virtually any scenario - but it does provide an incredible amount of convenience and benefit in the general sense. 

One thing to consider for a small minority of users who want to optimize ultimate system reliability, is to understand that automatic shutoff sensors inherently add an additional point of failure into a system. If sensors incorrectly interpret the shutoff action, the goggle can become nonfunctional when it otherwise would be.

 

Alternative Considerations - Warranty, Customization Options, Costs, Weight, Impact Strength, and Environmental Resistance

At the end of the day, it might not just come down to micro or macro features. These don't necessarily always determine completely important end user considerations, especially those that go into owning a goggle and not just using a goggle.

We briefly covered two of these alternative considerations above, which relate in part to the material of the system. The overall weight of the system is potentially very important to take into consideration, because weight is highly relevant to human performance (although not entirely dictated by material). Impact strength is also important for some users who might be involved in potentially riskier use cases. Again, impact strength isn't entirely determined by the material of the system, but it is heavily influenced by it. 

Environmental resistance can also be a factor, given that some goggles can be submerged in water for lengthy periods of time while others are merely water resistant (or not water resistant at all). 

Whether or not a device can be further customized, either at the time of purchase or in the future, may also matter to general users. Aftermarket compatibility with components like new lens designs are common for many night vision systems, but not all. In some cases, certain binoculars may not be compatible with all image tubes types, which could affect their ability to be changed or serviced in the future. 

Warranty support is always an important consideration and needs no real explanation. 

And finally, perhaps most important of all to many users, is the cost of the system. Costs will immediately provide a filter on what systems a buyer can even consider at all, and is the recommended starting point for all planning of night vision purchases. What can you realistically afford today? What about six months from now? Do you want to wait to save up to have a wider range of options, or are the options available to you now sufficient? Nobody can answer that question definitively, but the buyer themselves. Ultimately, though, we are happy to help guide you and provide options or recommendations based on any combination of features, costs, and alternative considerations. The best place to start might be  to contact us.