Aug 032014
The sun rises higher in the sky in summer, and travels around more of it, than in winter.

The sun rises higher in the sky in summer, and travels around more of it, than in winter.

Many of the preferred locations for prepper retreats are in areas that have substantial swings in temperatures between hot summers (daytime temperatures often in the 90s and sometimes exceeding 100) and cold winters (where temperatures seldom rise above freezing, even in the middle of the day).

That’s no big deal when you have unlimited utility power for heating and cooling, limited only by your ability to pay the electricity or gas bill each month.  But in a Level 2 or 3 situation, there won’t be any utility power, and creating our own electricity will be expensive and always in short supply.

We need to make our retreat structures as energy efficient as possible so as to minimize the need for heating and cooling.

There are lots of ways to improve the energy efficiency of our retreats, and most of these are totally ignored in ‘normal’ building design and construction because it makes little financial sense to, for example, spend an extra $50,000 when building your retreat, and to get a $500 a year saving in energy consumption as a result.  But in a Level 2/3 situation, the cost of the energy might rise from $500 to $5000 or more, and/or it might simply not be available at any cost, and so the financial equation changes drastically, making it more prudent for us to invest up front in additional energy-saving techniques in order to enjoy the benefits if/when we need to rely on our retreat and make do with less energy.

The good news is that not all these strategies need to be expensive or inconvenient, and some of them actually add to the livability of your retreat.  One such example is adding what in various forms can be considered either an awning, a brise soleil, a shade or a veranda (verandah – both spellings seem acceptable) to your retreat’s southerly (and much lesserly, east and west-facing) aspect.  (We’re not explaining what an awning, shade or veranda is because you probably know, but the term brise soleil might be less familiar.)

The clever aspect of such structures is that they interact with and take advantage of the way the sun rises in the sky.  In the summer, the sun quickly climbs up to a near vertical position before descending again at the end of the day.  In the winter, the sun slowly staggers part-way up the sky before sinking down again.  This difference is also more exaggerated, the further you move from the equator, and most of us are planning our retreats to be far from the equator.


Note – as shown above – the sun rises a bit north of east and sets a bit north of west in the summer, but in the winter it rises south of east and sets south of west.

It covers more of the sky in summer, and you might notice appreciable sun coming in from west and east facing windows, and possibly even a little bit in northern windows too.  But it is the southern facing windows that most need the sun shading.


What this means – and as illustrated above – is that some sort of shading/blocking structure that prevents the sun’s rays from shining onto and into our retreat while the sun is high in the sky will reduce solar heating during the summer – the time of year when we most want to keep the sun off our retreat and out of our windows.  But during the winter, when we’re keen to get all the sunlight and warmth we can, the overhead structure won’t interfere with the sun’s rays at all.  Heads we win, tails we don’t lose!

Because these devices take advantage of the varying seasonal location of the sun, they can be fixed in position, making them potentially robust and low maintenance.

How much sun angle should they block?  One approach is to see the maximum angle in the sky for the sun in mid-winter, the angle at the equinoxes, and block off all angles greater than the equinoxes.  You can get this information from this helpful website – simply put in your location and then choose 21 December as the date, and that tells you the maximum height the sun reaches at your location in the winter.

For example, in Kalispell MT (48º12′ north) the sun struggles to reach 18.4º up into the sky.  Compare that to the summer solstice (21 June) when it reaches 65.2º.  At the equinoxes (21 March and September) the sun goes up to 42.2º – a number which unsurprisingly is sort of halfway between the two other numbers.

One other interesting thing is to note that the sun has risen to 42.2º in mid summer by 10.10am and doesn’t fall below it again until 5.10pm.

So perhaps it makes sense to accept something around the 42.2º point as the transition from when we want to allow sun into the house and when we want to block it.  That gives us full sun for half the year, and successively blocks off more of the sun during the summer season.

This calculation should be modified by an appreciation of what type of heating/cooling needs you’ll have at the equinoxes.  Will you still be wanting to heat the retreat, or will you be starting to need to cool it?  That will also influence how much shade cover you want above your windows.


Having some type of permanent shade over your southerly facing windows is a simple way of ‘automatically’ regulating and cutting down on the sun’s heat that transfers inside your retreat during the summer while not reducing it during the winter.

It is probably the most cost-effective thing to do in terms of improving your retreat’s energy efficiency and reducing its need for cooling during the summer.  Be sure to include shading if designing a new retreat, and be sure to add it if purchasing an existing dwelling structure.

Aug 032014
Bigger is not always better with binoculars.

Bigger is not always better with binoculars.

One of the most useful pieces of ‘force multiplying’ equipment in your prepper kit is a good pair of binoculars.

Unfortunately, many people have little idea of what makes a pair of binoculars good or not so good, and with mass marketed binoculars usually being low quality, few people appreciate how helpful a good pair of binoculars can be when it comes to boosting your range of vision.  Furthermore, very few of the many different models of binoculars come anywhere close to meeting the requirements of a ‘good’ pair of binoculars, and so by statistical chance alone, most people end up having bought a poorly performing pair of binoculars.

There are many things to consider when choosing a pair of binoculars.  But these various issues are all easy to understand, and unlike evaluating high-end audio gear, for example – it is easy to tell if the binoculars you are considering are ‘good’ or ‘bad’.

Different Design Types

There are two major categories of binoculars to choose from.  One type is what we’d term ‘straight through’ binoculars (their official name is ‘roof prism’ binoculars) and they are distinguished by having more or less straight tubes from the objective lens (the big lens that faces towards what you are looking at) to the eyepiece on each side.

These binoculars also look similar to a third type of binocular, known as ‘Galilean binoculars’, but you’re unlikely to see them when looking for prepper type field binoculars and so we will pretend they don’t exist.  They are most commonly seen as opera/theater glasses these days.

The other major type is what could be termed ‘offset’ binoculars and which are more properly named Porro prism binoculars.  These have the eyepieces closer together than the objective lenses.

There are several reasons why we recommend you consider only offset type binoculars.  They can have larger objective lenses (read on to learn why this is important), they allow more light to pass through than roof prism binoculars (making for brighter images, particularly important in low light and night conditions) and the greater distance between the two objective lenses helps improve the stereoscopic perception and awareness of distance.  They also tend to be smaller in length, because the optical path travels in a sort of letter ‘Z’ through them rather than directly through them.

Note that there are also some very stupidly designed ‘reverse Porro’ binoculars, where instead of having the objective lenses spaced further apart than the eyepieces, they ‘zig in rather than out’ and are closer together than your eyepieces.  You will get less 3D depth perception with these, and we totally do not recommend them.

How Powerful Should Your Binoculars Be?

By ‘powerful’ we mean how many times magnification your binoculars may offer.  The answer to this question tricks a lot of people, including my parents, many years ago.

I remember as a young boy I desperately wanted a pair of binoculars, and so my parents gave me a pair one birthday.  Bless them, they wanted to get me the ‘best’ set they could, so they got a pair with 12x magnification.

But they did not understand that more magnification was not synonymous with better.  A 12x magnification was too much for hand-held binoculars.  The greatly magnified images jumped about too much and it was unpleasant to use the binoculars without some sort of steadying support.

So, to my parents’ surprise – and possibly to your surprise also, there is such a thing as ‘too much’ magnification.

On the other hand, there’s little benefit to get a pair of binoculars that only offers two or three times magnification, when there are perfectly good binoculars offering more than twice as much magnification.

To make a potentially long story short, the best compromise for portable handheld binoculars, between too much magnification making for too unstable an image, and too little magnification making for less overall value, seems to be at the seven or possibly eight times magnification.

 – Special Case – Fixed Observation Posts

Our earlier discussion about magnification assumed we were talking about a portable pair of binoculars that you would want to be able to use without the need for support.

If you are instead considering a pair of binoculars that could be mounted on a stand or tripod or other stable platform, and if weight issues are also not so relevant, then there is no reason not to consider more powerful binoculars.  In such a case, by all means get any power you feel appropriate, while noting that if the ratio between magnification and objective lens diameter gets too small, their value as night glasses will diminish appreciably (explained below).

Don’t go wild and crazy, particularly in a fixed OP.  In such a case, you know what vision ranges you need.  Maybe there’s a tree line a couple of hundred yards away, or a rise/fall in land that limits your vision.  You’re unlikely to want or need to be able to clearly see the buttons on a guy’s jacket a mile away, and if you do have that need, then you should use a special purpose telescope rather than binoculars.

Zoom Binoculars

Talking about magnification, you can also get zoom binoculars which might give you a magnification range from perhaps three or more times up to some massively greater number – indeed, we’ve seen zoom binoculars offering beyond-crazy maximum zoom capabilities, sometimes in excess of 100x.

The chances are your camera has a zoom lens, so you know how great they are.  So doesn’t it make sense to have a zoom function on your binoculars, too?

The answer to this is a very emphatic ‘No!’.

There are several reasons why zoom technology – so brilliantly wonderful on a camera – does not translate well to binoculars.

First, remember that any magnification greater than about 8x starts to become problematic from the perspective of keeping the image stable while hand-holding binoculars unsupported.

Second, greater zoom ranges start to get an inappropriate ratio between magnification and objective lens diameter (see below).

Third, a zoom lens has a lot of optical compromises in it.  These can be electronically processed out in a camera, but will be visible and problematic in a pair of binoculars.  The extra lens elements in the zoom will also add to the weight of the binoculars.

Fourth, remember that a pair of binoculars has two independent ‘telescopes’ that are joined together.  If you have a zoom capability, the zooming has to work identically in each ‘telescope tube’; if it doesn’t, then your eyes will be stressed and will lose the ability to merge the two images into one single image in your brain.  We’re unaware of any zoom binoculars on the market today with sufficient build quality as to avoid this problem.

Fifth, a zoom lens has a much narrower field of view, particularly at lower magnifications, than a regular lens.  This makes it harder to quickly point your binoculars at something you saw in the distance and be sure you’re pointing in the right direction, and also reduces the amount of situational awareness you’ll get because the area you are monitoring has shrunk.

We could probably come up with some more disadvantages too, but surely this is enough for you.  Don’t get a pair of zoom binoculars.

Well, actually, here’s one final consideration.  Because zoom binoculars are a gimmick that ‘serious’ users would never select, it seems that the leading manufacturers of binoculars don’t bother making them, so you’re restricted to lower quality suppliers of a product that is incapable of ever being high quality to start with.

Objective Lens Size

If you hold a pair of binoculars away from you and look through the eyepieces, you’ll notice that the image appears as a small circle within the broader eyepiece lens.

Here’s a key consideration.  You want the size of that small circle to be at least as big as the size of your eye pupil (the black circle in the middle of your eye).  Now, as you know, your pupil changes in size – in bright light, it gets smaller, and in dim light, it gets larger.

You want the size of the image to be bigger than the biggest size your pupil ever gets.  If it is smaller, then you are defeating the whole purpose of your pupil growing in size to admit more light in low light conditions.  On the other hand, if it is bigger than your pupil, there is no harm done at all.

Another benefit of a larger viewing image is that it makes it less critical to exactly center the eyepieces on your eyes, because even if your eyes and pupils are a bit off-center (compared to the binoculars – the ‘interpupillary distance’), they are still being fully exposed to the image within the eyepieces.

An adult’s pupil grows to about 7mm in diameter in low light (and as we age, it shrinks), so you want these circles to be at least 7mm in diameter.  Now – how do you know what size the circles are (other than measuring them)?

Happily, this is very easy to calculate.  Divide the diameter of the objective lens (the big one that faces towards what you’re looking at) by the magnification power, and that tells you the diameter of the image your eyes see.  For example, a set of 8×24 binoculars would have a tiny 3mm diameter image in each eyepiece.

Remember we said you should get binoculars with seven or eight times magnification?  Well, multiply those numbers by 7 to get the necessary objective diameters such binoculars should have – at least 49mm in the case of seven times magnification, and at least 56mm in the case of eight times magnification.

This is why the 7×50 binoculars have become pretty much the ‘gold standard’ and optimum compromise point for serious professional grade binoculars.  A pair of 8×56 binoculars would be slightly better in terms of magnification, but they’d also be appreciably heavier (the lens would have to be 30% bigger and overall, the binoculars would start to become too big, bulky and heavy for convenient use).

Field of View

Binoculars have a varying field of view, depending on their design and magnification.  The field of view relates to how wide an image you can see, and is generally specified either in terms of degrees, or in terms of how wide an image you get at a specific distance, for example, perhaps you might be looking at a pair of binoculars that offers a 5º field of view, or a 262.5 ft field of view when looking at things 1000 ft away.

To convert from degrees to feet (at 1000 ft) simply multiple the degrees by 52.5 (or divide the feet by the same 52.5 factor).  If you’re being quoted so many feet at 1000 yards, divide by 157.5 to get degrees (or divide by three to get feet at 1000 ft).

The wider the field of view, the easier it is to get sighted in on something, the easier it is to track fast-moving objects, and of course, the more you can see simultaneously.  The bigger the better for this parameter.

But remember that, in general, the greater the magnification, the lower the field of view.  Normally it is not appropriate to sacrifice magnification for field of view.  Decide the magnification you want first, then get the best field of view available for that magnification second.

Image Stabilization

If you have a heavy-duty budget for binoculars, you might be interested in considering a pair that offers image stabilization.  These are exactly as the name implies – they have built-in stabilizers that steady the image by adjusting the optics, and so allow you to enjoy handheld stable images with much greater magnification.

So that’s a plus.  But there are minuses.  As preppers, we want to have high quality but ultra-reliable gear, and adding all the micro electronics and electrical stuff that goes into image stabilization greatly increases the likelihood of sooner or later, something going wrong.  If the stabilization fails in a bad way – ie, one lens out of alignment with the other – then the binoculars become useless.

The image stabilization also requires battery power.  That’s probably not a deal breaker by itself, but it’s another pinprick of aggravation and hassle.  You’re probably also looking at another pound or more of weight because of the extra stuff inside.

The biggest argument against them though is that unless the objective lens diameter has grown in size to match the increased magnification, you are getting something that works only in bright light and which becomes increasingly useless in dimmer light.

We suggest you don’t buy an image stabilized pair of binoculars.  Spend the money on a truly high quality pair of standard binoculars – indeed, maybe you can even buy two pairs of standard binoculars for the same cost.


Maybe you’re not planning on dunking your binoculars in the ocean.  But how about using them in the rain?  A waterproof pair of binoculars will of course be more resistant to rain effects and humidity, as well as to accidental immersion in puddles or anything else.

Most higher quality binoculars are waterproof, indeed, let’s simply say that if the binoculars are not waterproof, then who knows what other design compromises exist, so don’t buy them.

As you probably know, there are varying degrees of waterproof capabilities, often expressed in terms of how many minutes at what depth of water can be withstood.  So don’t just assume that all waterproof claims are of equal validity – some will probably be better than others.

As well as claims about being waterproof, some binoculars claim to be fogproof.  This means they have probably had their interiors pressurized with moisture free nitrogen.  All fogproof binoculars are necessarily waterproof too, but not all waterproof binoculars are also fogproof.

Focusing Options

There are three types of focus offered on binoculars.  The simplest is a fixed focus that you can’t adjust, whether you want to or not.  The next most simple is a single or central focus knob that adjusts the focus in both sides of the binoculars simultaneously.

The least simple is having separate focusing controls for each side of the binoculars.

We’d suggest you do not settle for fixed focus.  While you probably don’t need to adjust the focus at all when switching between looking at something 75 yards and 150 yards and 300 yards apart, even with variable focus capabilities, if you occasionally use your binoculars to look at closer things, then you will definitely benefit from being able to adjust focus.

A fixed focus lens is a compromise that is slightly out of focus everywhere, and increasingly out of focus to the point of uselessness at short ranges.  Why would you ever want a slightly out of focus picture?  Isn’t the importance of the best possible image worth the slight hassle of turning a knob slightly?  Where is the logic of potentially paying $100-$500 more for a high quality pair of binoculars, only to degrade the image by settling for a fixed focus?

For hopefully obvious reasons, we definitely do not recommend having separate focus knobs for each side of the binoculars.  That is just way to inconvenient and complicated.  We might even prefer to have a fixed focus set of binoculars before accepting the double hassle of focusing twice each time we changed the distance between us and whatever we were looking for!

Some focusing systems involve turning a wheel/knob, around and around, to adjust focus, and it can take a fair while to do this.  Others have a ‘fast focus’ feature – some sort of lever that you only need to move a slight distance to go from closest to most distant focus settings.  That might seem like a benefit, but you lose the fine element of focus control with the turning knob, so we suggest you stick to a normal focus mechanism.

Next, let’s consider a related feature.

Diopter Adjustments

Most of us have one eye that is ‘better’ than the other, particularly as we age and our eyes start to deteriorate.  If you have corrective lenses, you are already familiar with how their degree of corrective strength is measured in diopters.

All good binoculars have a diopter adjustment on one of the two sides.  You use this to balance out your two eyes.  The way to do it is simple.  First, focus the side that does not have the diopter adjustment on something, with your other eye shut.  When you have that exactly in focus, close your eye on that side and open the eye on the other side, and turn the diopter adjustment to then get that side exactly in focus, too.

Once you’ve made this adjustment you won’t need to do it again, but of course if someone else uses your binoculars, they will want to adjust them for their own vision.  So it is helpful to make a note of your diopter setting, so when you get them back, you know where to set it without needing to go through the whole calibration process again.

It would also be a kindness, when passing the binoculars to someone else, to zero out the diopter adjustment for them.

Glass Coatings

Due to various interesting and complicated optical things, when light enters (or exits) a glass lens it gets slightly altered, and some light bounces back.  The bounced back light reduces the brightness of the final image you see through the binoculars, and the slight alterations create distortion in the image you look at.

So, to minimize these things, good  quality optics have coatings of special material on them.  You definitely want coated optics in your binoculars.

Now for the trick.  Some binoculars will describe themselves as having ‘coated optics’, some will say ‘fully coated’, some will say ‘multi-coated’ and still others will say ‘fully multi-coated’.

You can probably guess that the best is ‘fully multi-coated’.  Let’s explain what the others probably mean.

  • A claim for ‘coated optics’ probably means that some lens surfaces are coated with a single layer coating, but others have no coating at all.
  • A claim for ‘fully coated optics’ means that all lens surfaces have a coating, but it is probably only a single layer coating.
  • A claim for ‘multi-coated optics’ means that some lens surfaces have multi-layered coatings, but others probably have nothing.
  • And, of course, the ‘fully multi-coated’ means all lens surfaces have multiple coatings on them.  That is generally the best scenario to hope for.

One last thing about coatings.  Not all coatings are the same, and we have a suspicion that some low-priced low quality binoculars that boast of an optical coating have a fairly useless coating that does almost nothing at all to improve the image quality.  You can place your trust in the big brand names, but need to look at generic brands with extra careful scrutiny.

Optical Quality

It is hard to accurately assess the optical quality of a pair of binoculars just by looking at them, but there are some things you can readily see.  Here are several things to look for.

The first is to check there is no darkening of the picture around the edges.  You want even brightness all the way through.

The next is to check that everything is simultaneously in focus, both in the middle and at the edges.

Make sure straight lines are straight and aren’t curving (either in or out).  Move the lines (both horizontal and vertical) around – curving is most likely to appear around the edges of the image rather than in the center.

Next, look at a scene that has fairly bright light.  You don’t want any ‘flares’ or ‘streaking’ of the image.  Look around the edges of objects with light backgrounds, and make sure the object edges aren’t ringed with color fringes.

Now, hold the binoculars several feet away from you and look at the two small circles of image that you can see as if they were on the eyepiece lenses.  Rotate the binoculars so these small circles travel out to the edges of the eyepieces, and then have them travel around the edges in a big circle.  What you are looking for is to make sure that there aren’t squares inside the circles, greying out the gap between the outside of the square and the outside of the circle.  A little bit of this is probably okay, but you’ll see large differences in this effect between different binoculars.

Do these checks both when focusing on something up close and something far away.

Also, make sure that when you look through them, the images from both sides merge into one single image.  If they don’t do this, it is likely that one of the sides of the binoculars is out of alignment with the other side, and that will always (until/unless fixed) interfere with being able to comfortably and effortlessly use them as an extension of your own eyesight.

These simple tests will give you a degree of comfort as to the quality of the optics.

Construction and Ease of Repair

This is a bit more subjective, but do the binoculars appear to be solidly constructed and well made?  We prefer rubberized (sometimes called ‘armored’) type finishes, in the hope that if (when!) we drop them, the rubber surface will absorb some of the shock of having them dropped.  The rubber also quietens them – if something knocks against them, less sound will result, and that is sometimes helpful too.

One important test is to screw the focus adjustment all the way so the eyepieces move furthest out from the body of the binoculars.  Then lightly press on each of the two eyepieces and see if it wobbles.  It is important they stay solidly at the distance they are at, or else the varying pressure you’ll place on them during normal use will cause them to get out of focus with each other.  Poorer quality binoculars often display some weakness with this, good quality ones do not.

A similar consideration indicative of quality (or not) is you don’t want any slack or slop in the focusing mechanism, or in the way you can open up or close down the binoculars to adjust the distance between the eyepieces.

Are the two tubes held absolutely solidly in alignment with each other.  Even the slightest misalignment will interfere with your brain’s ability to blend the two images together.  Make sure that there is no susceptibility to any movement of either tube with respect to the other.

In terms of repair, can you readily access the interior of the binoculars and adjust the prisms?  If you drop them (we always have the carry strap around our neck so as to minimize the danger of dropping, and you should too) there’s a danger the prisms will be knocked out of alignment and you’ll want to be able to go in and try to realign them.  The prisms should not be glued in place, and you should be able to unscrew the parts of the binoculars to get inside.

Note that if you open up ‘fog proof’ binoculars, when you reseal them they will probably no longer be fog proof.  If this was an essential thing for you, you could at least flush them with wine bottle gas before sealing them up again, and that would displace much of the moisture bearing regular air.


This is a deceptive concept.  On the one hand, if you will be carrying binoculars with you, you want them as light as possible.  On the other hand, well-built and ‘solid’ binoculars will probably also be heavier.

That’s not to say that heavier binoculars are automatically better made and stronger than lighter ones.  We suggest you consider all other factors first, and only then, think about weight and possibly, if you are sure it is not compromising the quality of the binoculars, give preference to lighter weight.

Extra Features

Some binoculars super-impose a compass display so you know what compass bearing you are looking at.  That’s a moderately useful feature in theory, but the compasses are often much less than perfectly accurate, which greatly detracts from your ability to pass sighting data on to other people.  In addition, if you do not have the binoculars flat and level, the compass may not spin so freely.  Yes, you’ve got a $500 pair of binoculars with a 50c ‘toy’ compass inside – lucky you!

Some binoculars have ‘range finding’ marks on them a bit like rifle sights.  If you know the size of something you are looking at, the range finding marks help you to estimate its distance from you.  That may be a useful feature, particularly when away from home, because around your retreat, you’ll have of course already plotted out distances between all landmarks and relevant features (won’t you!).

Note that both compasses and range finding marks might be hard to see in the dark, and/or might require batteries for illumination.  We don’t consider either as a ‘must have’ feature.

Some binoculars have laser range-finders built into them.  That’s a lovely feature to have, but don’t get carried away and compromise on other features just to get the laser range-finder, because it is easy enough to buy a separate standalone laser rangefinder.

Indeed, we’d generally recommend you to get a separate unit, because it is probably much cheaper to do so – they cost about $100-$150 and are accurate to within a yard at ranges of potentially up to 600 yards, depending on what you’re trying to bounce the laser beam off (the bigger and more reflective the surface you are shining the laser at, the better).  Long range precision shooters love these devices.

Make sure the binoculars have lens caps for all four lenses, and also some type of carry case.  You want a neck strap for the binoculars and a second neck strap for the carry case.


We suggest you buy a good pair of 7 x 50 binoculars generally in line with the comments above.  Expect to pay over $100 but be reluctant to pay over $500 (based on August 2014 pricing on Amazon).  Although there definitely are some lovely binoculars available for much more money, you’ll get very good binoculars within this price range that you’ll be very happy with.

Aug 022014
The Surefire M1 is an inexpensive high quality IR Illuminator that works well with most night vision devices.

The Surefire M1 is an inexpensive high quality IR Illuminator that works well with most night vision devices.

In theory, a good night vision device will be operated in passive mode, and is able to brighten up very dimly lit scenes to a point where you can usefully understand what it is showing you.

In reality, many times this is not possible, either because there is too little light, or because the light, while present, is ‘wrong’.

By that we mean light sources in the background can drown out the details in the shadows of objects in the foreground, just the same way as when you take a regular photo of anything with a bright light in the background – the objects in the foreground are too dark.  When you have strong backlighting, you need to counter this with strong front lighting, ie from yourself, so as to get detail back into the shadows.  With a camera, you use a flash.  With a night vision device, you use a supplementary illuminator.

You need to realize that every shadow potentially contains a threat.  Any time you see an area of uniform black (and also any time you see an area of uniform white) that is not telling you there is nothing there.  Instead, it should be warning you that your Night Vision Device (NVD) is incapable of displaying whatever it is that might be present in that area of solid black or white (well, more commonly green, but you know what we mean!).

You should keep your NVD calibrated – both via settings on the device and by way of your use of supplementary light – so that everything in the area you are surveying shows some sign of greeny/grey rather than solid green/black.  Solid green/black obscures whatever it is in those areas and is dangerously deceptive.

So it is common – and necessary – for most NVDs to include a light source that you can switch on to actively illuminate what you’re looking at.  These light sources are always infra-red rather than normal white light.  This is so as to maintain a stealth factor and to keep whatever tactical advantage you might have by means of your NVD.  A normal visible light source would work perfectly well, of course, but using a regular flashlight makes your own presence obvious to any animal or person out there, and also allows anyone else out there to benefit from the light that it shines into dark spaces.

There’s another more subtle tactical advantage you’ve handed to any adversaries, too.  They can see where you are looking, and also, by clear inference, where you are not looking.  They know how to sneak past you (or how to sneak up and surprise you) based on clearly seeing what you are looking at.

None of these outcomes and tactical shifts are desirable.

Perhaps the worst part of this is that if the aggressors also have some way of seeing infra-red – their own NVD, for example, you’re at a double disadvantage.  They can surely see your beam of IR light, no matter how poor and primitive their NVD, but you don’t know they can see you.  Ugh.

Even if your adversaries don’t have any type of NVD, there is still a possible way you might risk disclosing your presence.  While the human eye can’t see infra-red light, some IR illuminators will glow, weakly, with a bit of a visible red glow that can be seen by the naked eye.  On a dark night, maybe the aggressors have adjusted their eyes to the low light and simply see the dim glow from your illuminator, even without needing to have NVDs of their own.

For all these reasons, we recommend you use illuminators very sparingly.  However, when you do need to use one, it is usually a case of ‘the brighter the better’ and you may find that the built-in illuminator on your NVD is inadequate.  So if you are going to use an illuminator, get a powerful and therefore probably separate illuminator (with a bit of luck, if the other side have low quality NVD gear, your powerful illuminator might even overload and destroy their gear!).

There are three things to consider when choosing a supplementary illuminator.

The first is its brightness.  As we said, generally, the brighter the better, but if you expect to be using this only at very short-range (ie within your retreat), too much brightness might overwhelm your NVD and cause everything to be white and washed out.  You’ll need to test any illuminators you get, and hopefully you’ll source them through a supplier with a generous return policy!

The second is how broad the beam angle is.  For short-range work, you want a broad beam at least as broad as the field of vision through the NVD.  This is so everything you are looking at is illuminated – you don’t want to leave any dark spots where surprises may be lurking.

If your requirement is for long-range illumination, you will want a narrower beam so that it carries further before getting too dispersed (and of course, the brighter the beam, the longer the range, too).

The third is the evenness of its beam.  This is very important – you don’t want a ‘doughnut of death’ where there is a bright ring of light but a dark patch in the middle.  Make sure the beam evenly illuminates everything within its coverage – this is even more important than with flashlights, because NVDs handle variations of light intensity and contrast within their image less well than our naked eyes do, and because of the ‘unreal’ or indirect nature of the image shown on an NVD display, you’re never quite sure if a dark patch is due to nothing being there or just a weakness in the NVD and the illumination that is driving it.

One other factor that few people consider, but which we think very important, is how the beam is switched on and off.  Depending on what you are using the illuminator with and what else you expect to be doing with your hands, you might find the best type of switch is a ‘momentary on’ switch.  That is, you press the switch and for as long as you are holding the switch down, the light is on, and as soon as you take your finger off the switch, the light goes off again.  This is much better than a switch that you press and release to turn on, then need to press and release a second time to turn off.  If things get ‘busy’ you might not be able to conveniently turn the light off again, and risk leaving the light on and drawing attention to yourself.

Of course this consideration is most relevant when using regular white light that everyone can see, but you should treat an ‘invisible’ IR beam as just as visible and dangerous to you as a regular flashlight, because for all you know your adversary also has NVD and your IR beam will appear like a huge searchlight shining into the sky when he looks in your general direction.

One more switching consideration.  It is really nice if there is a way to ensure the device doesn’t switch on accidentally when bumped – particularly if it is a ‘permanent’ on rather than a temporary on.  You might inadvertently have your IR beam on and not even realize it yourself!

A good general purpose illuminator is the Surefire M1 (about $120 on Amazon).  The former pre-eminence of Surefire for all types of tactical lighting products is these days under challenge by many new manufacturers, sometimes apparently offering better seeming products and at better seeming prices, but when you want to make a ‘safe’ choice and know, for sure, you are getting something built to the highest standards of quality and reliability, we feel that Surefire remains the best choice.

If you are wanting an illuminator for long-range surveillance, then you’ll find the M1 inadequate.  But a word of warning about long-range surveillance.  Don’t try to use your NVD further than it is capable of being used – there comes a point where the limits of resolution and the fuzziness of the image being displayed to you make it less useful, and no amount of extra illumination will make that any better.

For longer range purposes, we like the Luna Optics range of illuminators.  They also offer more expensive laser illuminators, but we’re unconvinced they offer better performance than the IR LED units.

The Deceptive Dangers of an Illuminator

We need to state something that we hope might already be obvious.  You already know that one danger of using an illuminator is that your adversary might detect the beam from the illuminator, creating a flipped tactical situation where they for sure know where you are (and also know what you’re looking at and so can avoid being there) while you have no idea at all if there are any adversaries out there at all.

The additional issue is in two parts.  Firstly, please understand that no matter how powerful an illuminator, it won’t show you something that you aren’t looking at and illuminating.  Secondly, the extra vision capabilities that you believe you are enjoying – and your inevitable feeling of having ‘tactical battlefield superiority’ is largely an illusion.  Do not abandon your defensive posture.

Using lights with NVDs is a bit like submarines stalking each other in the ocean.  All submarines have both active and passive sonar.  And, similarly, all submarines almost exclusively use only passive sonar.  It is only on rare occasion that a submarine will send out an active ‘ping’.  Although doing so might give that submarine useful battlefield data for a relatively short distance around itself, the sound of the ping will also reveal its formerly hidden location to all other submarines for a much greater distance around.

It is the same with illuminators, or lights in general.  Sometimes you have no choice but to use them, but when you do, the tactical situation changes massively and potentially unpredictably.

Static Illuminators

One scenario where illuminators might sometimes have a value would be if your retreat comes under attack at night and your attackers are hard to see in the dark.  In such a case, turning on external floodlight type illuminators, shining out from your retreat, would help you to see them more clearly.

But is this an overly complicated solution to a simple problem?  Why not use regular lighting, which means everyone in your retreat can see the aggressors without needing NVDs, and the aggressors are blinded by the bright lights which makes it difficult to see where you are, semi-safely located behind (and to one side, please!) of the lights.

A Lower Cost Alternative

Sometimes we become too reliant on technology, and certainly as preppers, we know the inherent dangers of this.  If you’re trying to get good vision of distant objects, don’t overlook the value of regular binoculars which can work well, even at night.

If you want to use binoculars at night, there’s one important thing to do – make sure that when you divide the diameter of the objective lens (the big one that faces towards what you are looking like) by the magnification factor, the result is at least seven.  This indicates the size of the image that you see through the eyepieces, and you want it to be sufficiently large to fill your eye pupils, so that at night, all your light collecting ability is being used.  The lower the number (for example, a pair of 8×40 glasses with the number 5 being derived) the less light collecting and the poorer they will work for you at night.

The classic binocular rating is 7 x 50.  This is close to the best all-round day/night portable binocular.


If your budget extends to night vision devices, you will need to also get supplementary illuminating devices so you can sometimes and selectively optimize the ability of your NVDs to reveal details of what is otherwise obscured in the dark shadows around you.

But using a supplementary illuminator can be a double-edged sword.  If an adversary also has NVD capabilities, your illuminator has clearly revealed your position and also shows where you’re watching, potentially giving a massive tactical advantage to your adversary.

For this reason, use such devices selectively and carefully.

Aug 012014
Our computers these days have many USB devices connected to them.

Our computers these days have many USB devices connected to them.

As preppers, we anticipate, plan, and prepare for a strategic failure in some part of our national critical infrastructure, no matter what the cause or what the specific failure may be.

Some risks are obvious.  But as prudent preppers, we also look to find and consider all risks, including those thought to be remote and unlikely.  Some risks are subtle and generally little considered, even though they could potentially be devastating in their consequences, and possibly might also be frighteningly possible.

An example of a risk category that few people fully consider is some type of cyber attack on our nation.  We’ve written about varying aspects of this in the past, most recently a mere week ago when we explain why the concept of a cyber-attack is so appealing to terrorists and others who wish us harm.

We don’t exaggerate when we say that almost everything in our lives is computerized these days, and the little bits that aren’t yet controlled by computers are quickly adding computerization and internet connectivity too.  While there are indeed benefits in having our kitchen appliances and our home heating/cooling all connected to the internet, there are also increased vulnerabilities.

The problem about anticipating and defending against a cyber-attack is that doing so requires a skill a bit like driving down the freeway at high speed, while only looking in the rear-view mirror.  On the freeway, the rear vision mirror will keep us in our lane, but only until the freeway curves ahead, and it won’t warn us if we’re closing in on the car in front.  With cyber attacks, we only know what our enemies have done in the past, we don’t know what they might think of next in the future.  Unfortunately, within even the simplest parts of any computer system lurk all sorts of unexpected vulnerabilities, sometimes overlooked due to the simplistic and ‘safe’ nature of the components.  It is impossible to be certain that we have identified – and solved – all possible computer vulnerabilities (even though some ‘experts’ claim they have done so).

For example, think of one of the wonderful enhancements to computer peripherals these days – USB connections and their ‘plug and play’ automatic connection between the thing we plug in and the thing it is plugged into.  A decade or more ago, this seldom worked as it should, and it was often referred to as ‘plug and pray’.  Nowadays the ‘intelligence’ within USB devices has been greatly improved and they are better able to correctly identify themselves and install the necessary drivers automatically onto the host device which they’ve been plugged into.

Unfortunately, as the ‘intelligence’ of USB devices has increased, so too has the ability to exploit that intelligence and re-task it for nefarious purposes.  A hacker could build a virus into the USB device’s ‘firmware’, and so when the device connects to your computer, it automatically loads itself onto the computer without triggering any of the typical anti-virus warnings.

Keep in mind that this type of attack could come not just from USB memory sticks and thumb drives.  We’ve known for some time about the ability of USB drives to come with a virus pre-loaded on them, and also of course, for a virus to copy itself onto a solid state USB drive, the same way as it could onto any other drive.  But this new risk is very different, because it doesn’t come from a USB’s available data storage.  It is hidden in the USB’s internal memory and drivers.  It could come from any USB device at all.  A mouse.  A keyboard.  A printer.  Look at all the USB devices you connect to your computer these days, and appreciate that all of them could be sources of infection.

Who would have thought you could get a disabling computer virus from your mouse or keyboard or webcam or whatever?

The problem is even worse.  Once on your computer, the hacker’s code can then copy itself onto any other USB devices it finds, and of course can totally take over your computer and do whatever it chooses with it.

The problem is even worse than this.  You might think ‘Okay, so I’ll only use USB devices I buy brand new in sealed boxes, and I’ll never share them with anyone else’s computers’.  But – who is to say that the company making the USB devices hasn’t been compromised – either deliberately or unknowingly?  Remember that much of the computer attacks that are directed at the US come from China, then look around your computer gear and see how much of that comes from China.  Ponder the implications of that, and you’ll quickly realize why the government is increasingly concerned about allowing Chinese computer hardware into sensitive installations (and also, to be fair, why foreign governments are increasingly anxious about allowing US hardware into their sensitive operations too!).  Even brand new untouched computer gear might be infected with pre-loaded malware.

This article explains the vulnerability and how there is no defense against it currently, saying

Most of us learned long ago not to run executable files from sketchy USB sticks. But old-fashioned USB hygiene can’t stop this newer flavor of infection: Even if users are aware of the potential for attacks, ensuring that their USB’s firmware hasn’t been tampered with is nearly impossible. The devices don’t have a restriction known as “code-signing,” a countermeasure that would make sure any new code added to the device has the unforgeable cryptographic signature of its manufacturer. There’s not even any trusted USB firmware to compare the code against.

We know, via Edward Snowden, that the NSA had some type of way of accessing computers through some type of USB exploit; it is likely that they may use some of these now publicly discovered vulnerabilities.  If the NSA is doing this, if Edward Snowden has disclosed that, and if there is now public discussion of USB vulnerabilities, how many hackers are also doing the same thing?

Unfortunately, at present, there is no known solution to this problem.  Your computer and your USB devices might already be infected.

A deliberate hacker attack could take the form of stealthily infecting as many computers as possible, and then having them all simultaneously fail on some future date.

Would that destroy our society and bring about the type of Level 2 or 3 scenario we plan and prepare for?  We’re not sure, but for sure the very best case scenario would be a massive economic and supply disruption that would see many services totally fail and much of the physical distribution of food and supplies also interfered with.  If computer based programs can no longer be used to manage agricultural processes, to plot demand and to schedule harvesting and processing, and to interface between the different companies in a complex supply chain, how will food efficiently make it from the field to the shelves of your local supermarket?

Without computers, what will happen to the banking system?  If your job involves using a computer, how will you and all your colleagues, customers and suppliers do your/their jobs?  If your company fails, what will happen to your job and your income?

The big unknowns are the nature and extent of a social collapse due to a failure of the nation’s computer resources.  We fear it might be worse than we hope, and so we plan accordingly.

We suggest you carefully read the article that explains the USB vulnerability and its implications, particularly the part that concludes

That means you can’t trust your computer anymore. This is a threat on a layer that’s invisible. It’s a terrible kind of paranoia.

Implications for Preppers

There’s not a lot of special things you can do to prepare for a broad attack on all our computers.  Your computers and USB peripherals might already be infected, and there’s nothing you can do about it.

All you can do is ensure that your retreat and your lifestyle can continue without any computerization, and keep your prepping at a necessary level in anticipation of a possible future Level 2/3 situation, no matter what the cause.

One thing in particular is to print out hard copies of as much of the electronic reference material you might have accumulated.  If your computers fail, you don’t want to have all your prepping knowledge resources destroyed.