Thermal Imaging for Surveillance

In this article, we’re going to take a look at using thermal imaging (or “thermal vision”) for surveillance purposes.

First of all, what do we mean by thermal imaging?

All natural and manmade objects emit infrared energy as heat.

Thermal imagers have many uses in hunting, surveillance, and equipment maintenance
Thermal imagers have many uses in hunting, surveillance, and equipment maintenance

With the right equipment we can detect the very subtle temperature differences of everything in view – and present it as a video image.

Thermal imaging technology reveals what otherwise would be invisible to the naked eye.

This sounds like exotic technology (and it sort of is) but you’ll also be surprised at just how capable and affordable these thermal vision devices have become.

Having said that – “affordable” is relative in this case.

This IR gear is more expensive than night vision devices that use Image Intensification methods that amplify ambient light.

There are also a lot of interesting uses of IR that aren’t just for surveillance – we’ll talk about those too.

Thermal Imaging let's you see an image based on the differences in temperature - here's an example where white is hot
Thermal Imaging let’s you see an image based on the differences in temperature – here’s an example where white is hot

Advantages of Thermal Imaging for Surveillance

Thermal Imaging has some substantial benefits over class night vision using Image Intensification.

Thermal imaging works in daylight or darkness – because that thermal energy is radiated at all times – and the devices aren’t too sensitive to use in daytime.

Further, IR devices won’t be blinded by bright light – they don’t “see” that light (except the IR component of it.

Thermal Imaging works in more diverse weather conditions – including fog, smoke, rain, and more.

Those weather conditions can be a challenge for classic I2 devices because those atmospheric conditions block or scatter the ambient light.

Lastly, thermal vision is very stealthy – as it can’t be used in complete darkness.

Thermal imaging excels at highlighting “hot” objects – people, animals, and vehicles (running or having recently run) all stand out against their cooler backgrounds.

A common use for thermal vision devices is the hunting of nuisance animals such as feral hogs
A common use for thermal vision devices is the hunting of nuisance animals such as feral hogs

Uses of Thermal Vision

OK, so now we understand what thermal vision can do – let’s talk about what we can use it for.

First of all, it’s a great surveillance tool – it highlights objects (animals, vehicles, people) at great distances.

Many IR vision devices include magnification of 20x or more – so this makes it easy to use remotely.

Many of these devices include photo or video recording.

Remember that these devices are creating a video image of the scene – so it’s trivial to record that.

(It’s also one of the reasons this tech is so much more expensive than I2 – there’s a lot more computing power involved.

IR Photography (thermography) is a whole subject by itself.

We can use the heat emanating from objects to determine if someone has a fever, if equipment is working properly, or to find hotspots.

In fact, you can use an IR camera or vision device to look for unexpected devices – like hidden spy cameras and other spy gear.

Let’s move on and look at some thermal vision hardware next.

We also need to highlight one more important point.

ITAR Regulations Prohibit Export Of Thermal Imaging Devices

You may have heard of ITAR – the International Traffic in Arms Regulations of the United States.

These were setup to control the export and import of defense-related articles and services.

And in particular – thermal imaging devices fall under these regulations.[1]

ITAR is serious business – and can result in jail time.

As a US citizen there are no laws against buying and using thermal imaging devices.

But, it is illegal to export, sell, or even to let a foreign citizen use these (or the manuals!).

So, be careful – and know what you are doing.

Thermal Vision Devices

Let’s look at some gear.

Monoculars are like a miniature telescope – meant to be used with one eye – in case that isn’t clear.

What are the benefits of this sort of device?

Because it’s one tube it’s lighter, smaller, and easier to deploy.

You don’t really get any proper depth perception from these sort of devices anyways so a monocular is a very popular choice.

These can be used hand-held or tripod mounted.

Theoretically you could helmet mount this as well – but IR imaging doesn’t really work well in that role.

A binocular has two eye pieces and is meant to be used just like traditional binoculars.

They will be heavier, harder to pack, and probably have less battery life (unless they have proportionately more battery.

Binoculars are primarily used hand-held – or mounted on a tripod.

Rifle scopes are also a popular form factor for thermal vision.

This is a no-brainer for using this tech for hunting nocturnal nuisance animals.

IR Cameras are also available – these are lenses or other gear that let you take IR images.

These are used for hotspot detection in electronic equipment, and many other purposes.

Thermal Imaging for Surveillance – In Summary

Thermal vision is advanced technology that you can use to see in total darkness or in almost any other conditions.

It has become quite small, durable, and affordable (relatively speaking).

Check it out today and see what you can do with thermal imaging gear.


Some photos are property of the manufacturer, and provided by the manufacturer.

1. The International Traffic in Arms Regulations (ITAR) – Title 22, Code of the Federal Regulation, Parts 120-130.