The thermal camera is a wonderful invention, but what myths, legends and other information don't you know about them?
Becoming increasingly more affordable, thermal imaging equipment is rapidly becoming adopted in many different industries from marine iceberg detection to automated process machinery monitoring. They're also extremely common in building analysis, detecting electrical components that are overheating and countless other applications.
A thermal camera is used to detect how heat is distributed across an environment. In basic terms, a thermography tool detects heat rather than light, displaying this information as a heat-map image with relavant temperature data. Whereas every pixel of a digital image is assigned a visual marker, a pixel for a thermal image is assigned image and temperature data, allowing the heat map to be created.
But what can (and can't!) these cameras do? Read on to find 5 amazing things you didn't know about thermal cameras!
6. They CAN'T See Through Glass
Take a shot out of the window with your phone. What do you see? You'll see what's outside your window (provided there's no glare, naturally).
If you were to replicate the same shot using a thermal camera, all you'd get is a shot of yourself holding the camera, plus temperature information.
Why does this happen? Well, the camera is trying to read temperature data, so what it picks up on is not what's through the glass, but instead is the reflected temperature coming off objects in the room, plus the user's body temperature. This is because glass is a reflective material; the same principle would also apply if you took a thermal image of someone wearing glasses (it'll usually look like they're wearing some cool shades).
The scientific answer to this question is a lot more tricky; whereas windows allow visible light through them, they're designed to block IR (infrared) light (another part of the light spectrum) from passing through it. This turns the window essentially into an infrared light mirror; hence the reflection.
With a high-end, professional-grade camera it might just be possible to see through the glass, but the quality of the image would degrade significantly because of the glass filtering out infrared information.
5. It's (Nearly) Impossible To Hide From a Thermal Camera
Sorry Predator fans - Arnie would have been killed almost instantly by the alien if he caked himself in mud to stay invisible.
As a thermal camera doesn't rely on visible light to create an image (instead using heat to create what it displays) it is not affected by darkness, weather conditions or other things that may not be picked up on - for example - by nightvision equipment.
This is why police and security professionals are rapidly becoming more reliant on thermography; the technology allows them to easily spot criminals in areas they shouldn't be, or to track them through complete darkness. The military also commonly uses thermal equipment in both their aircraft and fieldwork to detect body heat and ensure the safety of soldiers.
Even if you were standing in a bush in fog, a thermal camera would more than likely see your body heat amongst the foliage. This is why hiding from a thermal camera is particuarly tricky, especially if the cameras are high specification. It is, however, possible, as proven by the Mythbusters crew.
On a special episode, the Mythbusters tried all kinds of trickery to beat thermal cameras including Arnie's mud trick and increasing the temperature of the room to evade a security thermal system. None worked, until they decided to employ the use of a glass sheet.
As we said in the last point, the thermal camera can't see through glass, making a large glass sheet ideal for evading a thermal camera directly ahead of you. Unfortunately, this would mean wearing an all-over glass suit if you had thermal cameras pointing in multiple directions.
4. Absolutely Everything Can Be Measured Using Thermal Cameras
We all know our own bodies output heat, but did you know that absolutely everything in the world does as well?
Unless an object is at absolute zero (which is -459.69°F) is emits a small amount of infrared (IR) radiation. Depending on the sensitivity of the thermal camera you're using, even the most minute changes in temperature can be detected, so if an object is above absolute zero, it can register on a thermal camera.
The way an image is displayed varies greatly depending on what it's pointing at; a red hot pipe will be extremely vivid in colour (red/orange), while something cold will appear for muted and blue/purple.
From your desk at work to extremely cold ice cream - every object in the world above absolute zero will be able to be found and displayed on a thermal image.
3. Ghostbusters? Not Likely.
If you watch a ghost hunting programme, chances are they'll break out a thermal camera at some point as a hunting tool. It certainly looks high-tec and useful for spotting hidden temperatures, but in reality a thermal camera is not really a useful ghost hunting tool.
As a camera can be affected by so many different temperature sources, anomalies on the camera can usually be explained by normal phenomenons, such as heating behind walls, or even reflected temperature from a human's body heat.
A famous example of the latter comes from the popular ghost hunting programme TAPS. In this video, the hunters claim to see a ghostly figure in a locker doorway using the camera. In reality, what they're seeing is the reflected body heat of one of the crew shining off a reflective surface.
That's not to say that these cameras might be able to pick up weird things, but be a bit dubious when they're using them on these programmes!
2. They CAN'T See Through Walls
We often get asked if a thermal camera will be able to see through a wall. The short answer is no, except in extreme cirumstances.
As most walls are thick to keep a building insulated, a thermal camera has no way of picking up on the heat on the other side of the wall. What you're likely to see instead is the heat of the wall, caused by factors such as internal heating, light exposure and air conditioning. You may, in rare occasions, be able to see the heat of pipes on the other side of the wall (depending on the camera used and the wall in question).
Unless the wall was almost paper thin, you'd really struggle to see anything on the other side using a thermal camera as they simply can't penetrate the wall's thickness.
1. There's So Many Uses For A Thermal Camera
Did you know that thermal cameras are now often mounted on ships to help them spot icebergs and overboard passengers? Did you know firefighters use them to save lives? Did you know that some cameras can even detect gas leaks?
The uses of thermal cameras are vast; here's just a few examples of how these instruments are used all over the world:
- Home and building inspections - spot moisture damage, detect poor insulation and more
- Marine use - used by both military and commercial vessels to aid with detection of icebergs, enemy ships and warm bodies in the water
- Electrical inspection - find overheating components and take remedial action before they become a problem
- Law enforcement - police use these cameras to track criminal body heat on foot, in vehicles and from the air
- Security - CCTV thermal installations can see through darkness and create 360 degree surveillance networks
- Process - monitor production lines constantly for problematic components and overheating issues
- Medical - spot tissue damage and fever conditions in both human and animals
Isn't it about time you got yourself one of these great tools? Visit our Thermal Camera section for the latest and greatest cameras.