The FLIR E60 is our pick for the best thermal camera, with its excellent resolution and accuracy, impressive set of auxiliary features and support for radiometric JPG image format.
Our step up pick is the FLUKE Ti400, with its range of auxiliary features, excellent performance and wide temperature range.
Our budget pick is the FLIR E4, which offers you great performance for basic applications at a price that does not break the bank.
A Little Background
Thermal imaging cameras, also known as infrared cameras, are powerful devices that allow you to create images from information that cannot be perceived by the naked eye. Unlike standard digital cameras which create images from the visible part of the electromagnetic spectrum, thermal imagers create images from infrared radiation. The main difference between a thermal and a standard camera is that standard cameras operate within the 400- 700 nanometer wavelength range, while thermal imagers operate at wavelengths of up to 14,000 nanometers. A thermal camera is fitted with IR-sensitive sensors which detect and visually represent differences in temperature.
How They Work
Before we get into how thermal imagers work, it’s important to first understand the physics of light. Light is emitted in waves. Each light wave has a specific wavelength depending on the amount of energy in the light wave. The more the energy in a light wave, the shorter its wavelength. Visible light contains a spectrum of 7 colors, with red having the longest wavelength and violet having the shortest wavelength. The visible light spectrum also has InfraRed (IR) and UltraViolet (UV) spectrums on each side of it, which are invisible to the naked eye. When capturing thermal images, we are interested in the IR spectrum.
The IR spectrum is split into 3 categories. The first one is Near IR, which is closest to visible light and ranges from 0.7 to 1.3 microns in wavelength. The second category is Mid IR. This has wavelengths of 1.3 to 3 microns and is commonly used in everyday electronics such as remote controls. Finally, we have Thermal IR, which ranges from 3 to 30 microns in wavelength. Thermal IR, also known as heat, is the largest part of the IR spectrum. Unlike other categories which are reflected off objects, thermal IR is emitted by objects. Thermal cameras depend on thermal IR to produce images.
A thermal camera is fitted with a special lens which focuses the thermal IR being emitted by all the objects within its field of view. The focused thermal IR is passed through a heat detector or microbolometer, which creates a highly detailed temperature pattern known as a thermogram. The thermogram is then converted into electric impulses which can now be translated into a visual image on the device’s display.
Uses of Thermal Cameras
Thermal cameras have a number of uses in the diagnosis of problems and performance of preventive energy appraisals and maintenance. Some of the most common uses include:
Heating and cooling issues: Having an HVAC unit is of no use if your house has poor insulation or faulty seals around the windows and doors. These problems will cause both cool and hot air to escape rapidly and let in air from outside. This in turn overworks your HVAC system and significantly increases your energy bills. With a thermal camera, you can inspect your house and find any areas that have faulty insulation.
Circuit boxes and wall outlets: Electrical problems will not only cause expensive repairs and damage your electrical devices, they also pose a big risk to your life. You can use a thermal camera to detect any overheated circuit boxes and wall outlets, thereby helping you discover any looming electrical problems before it becomes too late.
Plumbing issues: One of the greatest problems with plumbing is that you cannot see what is wrong with the pipes or where the clog is. With a thermal camera, you simply need to get hot water flowing through the pipes and you can follow in real time to see where the clog or leak is.
Roofing problems: It’s important to keep your roof well maintained and repair any problems as soon as they arise. Unfortunately, detecting the problem with your naked eye is not an easy task, especially without having to go up onto the roof. However, with a thermal camera, you can easily detect problems from the ground level. The device will show you spots where heat may be escaping or leaking spots that let in water into the ceiling.
Animal health: When an animal or pet has a health problem, pinpointing the location of the specific problem can be challenging. Luckily, heat is a good indicator of problems within the body, especially problems such as infections, inflammation and fevers. A thermal camera can show the hot spots within the animal’s body, allowing you and the vet to easily pinpoint which areas you should focus on in the diagnosis.
Water leaks: Water leaks can cause a lot of damage to your home, such as decayed wood structures and potentially dangerous structures such as roofs, foundations, slabs or basements. You can use a thermal camera to catch water leaks and detect puddles, especially when they are hidden behind walls.
Security: Thermal cameras can help you detect intruders hiding within your compound, especially at night. When you are out camping, they can also help you watch out for any dangerous animals within your campsite.
First responders: Thermal cameras are very useful in emergency situations. For instance, firemen use them to locate victims trapped inside a building and to navigate within buildings filled with dense smoke. Victims buried under collapsed structures and debris can also be located using these devices.
Auto repair: Just as with home electrical systems, overheating is an indicator of problems when it comes to car engines and car electrical problems. You can use a thermal camera to pinpoint the source of the problem, saving you a lot of time and unnecessary disassembly.
How We Picked
To find the best thermal camera, we spent several days researching and testing a wide range of top brands. In our research, we considered the following factors:
Image Quality/Resolution
This is one of the most important things to consider before purchasing a thermal camera. Higher resolution devices provide more detailed images and can detect temperature differences from a greater distance. However, don’t compare a thermal camera’s resolution to that of your smartphone camera. The best thermal cameras have a resolution of about 0.08 megapixels (320 x 320 pixels), which is a far cry from what you would expect of a standard digital camera.
In some instances, there is usually confusion between the resolution provided by the thermal detector and the resolution of its LCD display. We tested all the devices and ascertained that the listed resolutions are from the thermal detector.
Sensitivity
This is another important factor to consider when purchasing a thermal camera. This refers to the temperature range within which the device operates as well as how sensitive it is to temperature changes. The more sensitive it is, the more capable it is of recording even the finest temperature changes. Sensitivity is measured in degrees. The lower the number, the more sensitive the device. The devices we tested were in the 0.05 to 0.15 degrees range. While this seems like a very small difference, it can make a big difference when you are dealing with intricate electronics.
The best thermal cameras can detect temperatures ranging from -20 degrees Celsius to about 1200 degrees Celsius. Basic imagers operate in the -20 to 250 degrees Celsius range, which is more than enough for most home inspection applications. When buying a thermal camera, it would be best if you look for one that operates within the temperature range of the environments where you will be using it.
Durability
This is a very important factor to consider since thermal cameras are often used in harsh, industrial environments. Some measurements will also need to be taken under equipment or in awkward spots, increasing the likelihood of the device getting dropped. Considering the price you have to shell for one, you have to ensure that the device is impact resistant. It’s important to note that durability depends on its design rather than some specific features.
Battery Life
The last thing you want is to have the battery die when you are out in the field. Most thermal cameras have a standard battery life of about 4 hours, while the charge time can vary anywhere between 2.5 and 4 hours, with 2.5 hours being the standard. Some models also come with a spare battery pack, which comes in handy when you have to work for long hours without the time to stop and recharge your battery.
Auxiliary features
The best thermal cameras have some extra features which give you some extra convenience when using them. However, this does not mean that a basic device without these features won’t serve you perfectly well. Some of the auxiliary features we considered in our research include:
Digital camera: The best imagers come equipped with a digital camera as well, allowing them to capture IR and visible light images simultaneously. This makes it easier to locate the problem area, since the IR image is mapped directly on top of the visible light photo. Apart from having an inbuilt digital camera, the best devices also often have strong inbuilt LED flashlights, which are useful for lighting up the visible light image in dark environments as well as finding your way in the dark.
Image presentation: The best thermal cameras on the market have the capability to save the captured infrared images, with most being capable of saving at least 1000 images, depending on the image format. The saved images can be transferred to a computer through a SD card reader or a USB cable. If the device has an inbuilt digital camera, the images can either be presented as an IR image on top of the digital image (picture-in-picture) or as a blend of the two images (fusion). Some devices are also capable of recording video. This can be very useful when you want to view temperature patterns over time.
Focus: If IR images are to be of any use, they have to be clear. Different devices have different ways of dealing with this. Most budget models come with a fixed lens, which means that you cannot change the focus. Such devices are usually in focus when they are 4 feet or more from the target. As such, they are good for scanning large areas, but become a limitation when used very close to the target area. Others have a manual focus. They have a focus ring which allows you adjust the focus depending on your distance to the target, allowing you to capture the optimal image. The best thermal cameras are equipped with autofocus, which allows the device to automatically focus on a target at the push of a button. Autofocus cameras also have a manual focus ring, giving you complete control.
Annotation: When using a thermal camera, sometimes you will find it necessary to take up some notes. Carrying around a clipboard out in the field can be cumbersome, while matching up your notes to the images can be time consuming and confusing. To make this easer for you, some models allow you to add some notes alongside the image. This can be done through text, voice or sketches.
Compatibility tools: One feature that you will find particularly useful is the ability to wirelessly link together your device with other tools such as a clamp meter or moisture meter. This allows the imager to directly add data from the peripheral tool onto the image data, making it easier to understand and report the problem.
Connectivity: A good thermal camera should have the capability to connect to various computer equipment. Some can connect wirelessly to your smartphone, while others can stream video to a computer which can be in turn connected to a large screen for unbeatable presentations.
Other features: Some other auxiliary features we considered in our research include digital zoom, laser pointers, durability and the ability to use telephoto and wide angle lenses.
Our Pick
Our top pick for the best thermal camera is the FLIR E60. This device is a combination of excellent build quality, high resolution and high accuracy images and great features that make capturing and sharing images very convenient. The E60 is an uncompromising model that does not sacrifice features and resolution in order to lower the price.
One of the most notable features of the FLIR E60 is the resolution. The device has a resolution of 320 x 240 pixels. While this may seem ridiculously low for a standard camera, it is actually quite high for a thermal imager. Thermal cameras use sensors that are way different from the typical sensors used in standard cameras. If they were made at similar resolutions to standard cameras, they would be exorbitantly expensive.
To supplement the details of the low resolution IR images, the FLIR E60 has an onboard digital camera with a resolution of 3.1 megapixels. Apart from providing supplementary details for IR images, this digital camera can also be used to capture standard photos which are useful for providing overall content of the scene. The E60 comes with a manual focus which allows you to control the quality of your IR images. While it would have done better with autofocus, you will quickly get the hang of using the manual focus.
Another thing we liked about the FLIR E60 is its image format, which is among the most convenient. Unlike many other devices which force you to save and view your thermographic data in proprietary file types, the E60 saves its images in radiometric JPG format. These files can be saved and viewed on virtually any device or platform.
One notable thing you will like about the FLIR E60 is its precision and sensitivity. The device has a sensitivity of 0.05 degrees Celsius. This means that the E60 can distinguish between areas that have a 0.05 degree temperature difference. This was the highest sensitivity among all the devices we reviewed. The E60 also has quite a large temperature range. According to FLIR, the E60 can work in the range of -20 to 650 degrees Celsius. This range is enough for most of applications. The E60 has an accuracy of 2 degrees Celsius.
When it comes to auxiliary features, the FLIR E60 has almost everything you would wish for in a thermal imager. Firstly, it comes with Wi-Fi connectivity, which comes in handy when you want to share files quickly. It has video capture capabilities for when you want to capture real time changes in temperature. It is equipped with an illuminator lamp and a laser for easy target acquisition and allows you to take quick voice and text notes. It also comes paired with Android and iOS applications which are very convenient when you want to transfer, organize and share information.
The FLIR E60 uses a lithium ion battery which keeps it running for up to 4 hours of shooting. Unlike most other devices, the E60 also comes with an extra battery pack and an external charger. This allows you to keep working for long without the need to stop and recharge. The E60 has a superior design and has both drop and splash protection.
The E60 costs a fortune, and as such, it needs a proportional warranty. Luckily, FLIR offers a very generous warranty for the E60. Once you purchase the E60, you get a 10 year warranty for the sensor, a 5 year warranty for the battery and a 2 year warranty for the parts and construction. If any of these parts malfunction during this time, you will get repairs or replacements free of charge.
FLIR E60 Specifications | |
IR Resolution | 320 x 240 pixels |
MSX Resolution | 320 x 240 pixels |
Sensitivity | 0.05°C |
Accuracy | ±2°C |
Video Cam | 3.1MP |
Zoom | 4x continuous zoom |
Focus | Manual |
Uncooled Microbolometer | Yes |
Color LCD Touch Screen | 3.5” |
MSX | IR image with enhanced detail presentation |
Flaws but Not Deal Breakers
The only major downside to the FLIR E60 is that it does not have autofocus. However, this is not really a deal breaker because you will soon get the hang of using the manual focus. The only other downside is the hefty price tag. However, if you willing to part with a fortune, this is easily the best thermal imager you will find on the market.
Step Up Pick
The FLUKE Ti400 is another impressive device with great performance, excellent resolution and a nice set of auxiliary features. The Ti400 comes with an IR imaging sensor that has a resolution of 320 x 240 pixels. It is also equipped with a 5 megapixel onboard digital sensor which captures visible light images at the same time you capture IR ones. You can choose to either view the standard images separately or overlay the IR image on top of the standard image.
To help you capture sharp high resolution images, the FLUKE Ti400 has an autofocus system. However, it still has a manual focus in case you want total control. Like many other high-end devices, the Ti400 can detect temperature changes of up to 0.05 degrees Celsius. The Ti400 also has an impressive temperature range of -20 to 1200 degrees Celsius. This means that the Ti400 can be used in almost any application you can think of.
The FLUKE Ti400 also has some impressive set of features. It comes with built-in Wi-Fi connectivity for quick image sharing. It has video capturing capabilities, a laser pointer, voice and text annotations and an illuminator lamp. Like most devices, the FLUKE Ti400 comes with a lithium ion battery that can provide up to 4 hours of shooting time, as well as an extra battery and an external charger. The device has a solid build with water, dust and drop protection.
The FLUKE Ti400 loses out to the FLIR E60 because of its drawbacks in imaging performance. Unlike the FLIR E60 which uses radiometric JPG format, the Ti400 stores its images and data in a proprietary IS2 format. While this does not compromise the actual quality of the images, the images can only be opened by someone with FLUKE’s software. This makes sharing the images with others more of a challenge. Unlike the FLIR E60, FLUKE were not very generous with the warranty either. With the Ti400, you only get a 2 year warranty.
Budget Pick
If you are looking for an inexpensive yet high quality and powerful device, the FLIR E4 is a great choice. While its image quality and extra features cannot be compared with the big boys, it is still a handy device for most basic applications. The E4 has a sensor that captures IR images at a resolution of 80 x 60 pixels. While this resolution is below the standards stipulated by the Residential Energy Services Network (RESNET), it is still enough for analyzing general areas for potential problems. With the FLIR E4, you can identify problems like overheating generators, serious leaks and large gaps in insulation. However, you will need a more powerful device for more intricate details.
The E4 comes with a 0.3 megapixel onboard visible light sensor which supplements the images from the IR detector. This helps improve the clarity of the E4’s images. The E4 has a fixed lens focus. This means that, to capture the sharpest images, you will have to adjust your distance to the target. Fortunately, the lens is optimized for the greatest possible distance, therefore this will not present much of a problem.
Images captured on the FLIR E4 are saved in a standard JPG format, which can be opened and viewed on almost any device. However, the images do not have any embedded radiometric data, therefore they do not have the wealth of information you would expect from higher end models. In spite of this, the images will still help you identify and analyze general problem areas.
In spite of the startlingly low price, the E4 has the same solid design and build you would expect of other FLIR devices. It is built for durability, with a rubberized outer shell that makes it resistant to falls of up to 6.6 feet. Just like other FLIR devices, the E4 is covered by a 10 year warranty for the detector, a 5 year warranty for the battery and a 2 year warranty for the parts and construction.
Best Thermal Camera for Home Inspections
The Extech i5 is a compact and fully automatic device that is ideal for home inspections and facility maintenance. The Extech i5 is very user-friendly, which makes the device of choice if you do not have a lot of experience using thermal imagers. The Extech i5 is small and light (weighs just 12 ounces), making it a good option for single-handed operation. It comes with a rechargeable lithium ion battery that powers the device for up to 4 hours of shooting time and is equipped with a 2.8 inch LCD color screen. The Extech i5 has a fixed lens focus which automatically focuses on anything from a distance of 2 feet or more.
The Extech i5 comes with QuickReport Software, which helps in the analysis and sharing of radiometric images. It has a rugged body that allows it to withstand a couple drops. It has an internal memory which can save up to 5000 images. The Extech i5 has a 2 degree Celsius accuracy and can detect temperature differences anywhere from 0.1 degrees Celsius. The Extech i5 comes with a 2 year limited warranty.
Best Thermal Camera For Fire Fighting
The FLIR K2 is a device that is specifically designed for use by fire fighters. It is useful for detecting temperature changes, determining temperatures within structures, locating trapped people and pets and assessing safety before going into burning structures. The K2 is built to withstand the extreme conditions faced by fire fighters in their day to day operations. It is rugged and reliable, with an IP67 water resistance rating and the ability to survive 2 meter drops onto concrete. It can be used for up to 3 minutes in temperatures of up to 260 degrees Celsius. It has a temperature range of -20 to 500 degrees Celsius and an interface that is comfortable to use with a gloved hand.
One thing you will definitely like about the K2 is that it is equipped with FLIR’s patented MSX technology. This enables the device to emboss important details from the onboard digital camera onto the IR images, providing extra context and perspective for easier orientation and safety. The detector on the K2 produces 160 x 120 pixel images, which can then be viewed on the sharp 3 inch LCD display. The K2 also supports 7 different imaging modes. You can easily switch between these modes using the FLIR Tools Software. The device comes with a quick-release battery and is covered by FLIR’s 2-5-10 warranty.
Best Thermal Camera For Electrical Inspections
The FLUKE FLK-TIX520 60HZ is a top of the range device that is built for advanced troubleshooting and maintenance applications in large buildings and factories. It comes with an IR sensor that produces images at a resolution of 320 x 240 pixels. It is also equipped with the SuperResolution software which is capable of upscaling the images to a resolution of up to 640 x 480 pixels. This makes the images clean and clear for easier and exact problem identification. The images can be viewed on the 5.7 inch responsive touch screen. To allow for images in tight situations, the lens has a 180 degree rotation angle.
The FLK-TIX520 is equipped with a laser distance detector which is useful for measuring distances to the target. The device also has video capabilities for real time detection of temperature changes. The videos can easily be streamed via Wi-Fi of HDMI. The FLK-TIX520 comes with autofocus to ensure optimum image quality. However, you can still use the manual focus. The FLK-TIX520 comes with a 5 megapixel onboard visible light sensor which takes standard photos for picture in picture image presentation. The device is highly sensitive, with the capability to detect temperature changes of up to 0.03 degrees Celsius. It also has an impressive temperature range of -20 to 850 degrees Celsius. The FLK-TIX520 comes with a laser pointer, a 4GB internal flash memory and voice and text annotations capabilities. It supports multiple file formats, can withstand drops of up to 1 meter and comes with a 2 year standard warranty. The only downside to the FLK-TIX520 is that it is quite costly and the warranty is not very generous.
Best Thermal Camera For Leak Detection
The Black & Decker TLD100 is a device that is built specifically for leak detection. It is a simple, user friendly device that determines surface temperatures using an infrared sensor. At only 16 ounces, the TLD100 is lightweight and has an ergonomic pistol-grip design. To use the TLD100, you need to take a reference temperature of a surface within your house, for instance a neutral wall. From there, the TLD100 will give you the surface temperature of anything you point it at in reference to the base temperature. If a surface is hotter than the reference temperature, the device will glow red. If the surface is cooler than the reference temperature, the device will change to a blue glow. It will also show you the exact temperature reading of each surface as you scan.
Temperature readings are displayed on a 1 x 1 inch screen. A switch located in the battery compartment allows you to toggle between Fahrenheit and Celsius readings. The TLD100 allows you to set the temperature threshold to either 1, 5 or 10 degrees. If you set the threshold to 10 degrees, the device will show a leak detection when there is a 10 degree difference from the reference temperature. Same case applies for 1 and 5 degrees. The TLD100 has a temperature range of -22 to 302 degrees Fahrenheit, a 0.1 degree accuracy and a 6:1 field of view. The TLD100 uses a 9V battery and has an auto shut-off feature to conserve battery life.
Best Thermal Camera For Smartphones
If you are involved in a lot of construction and home improvement projects that require you to detect heat and moisture but don’t have the money to splurge on an expensive device, you can turn your smartphone into a thermal imager using the FLIR One Pro. The device, which is a self-contained dongle, connects to both android and iOS smartphones through the Type-C port.
The FLIR One Pro has an IR sensor that captures images at a resolution of 160 x 120 pixels to ensure a crisp representation of thermal information. The device is also equipped with an onboard 1440 x 1080 pixel VGA visible light sensor. The images from the two sensors are blended using FLIR’s MSX technology to add extra detail and edges to the final image. This way, you can see the outlines of the object and the heat signature instead of abstract multicolored blobs. The FLIR One Pro also comes with VividIR technology, an image processing technology that upscales the images for impressive clarity.
The FLIR One Pro is paired with the FLIR One app, which can be downloaded for free from the App Store. The device has an internal battery that is charged through a Type-C port. The battery keeps the device running for up to one hour of shooting, though it will drain much faster if you are taking videos. Recharging the battery takes about 45 minutes.
The FLIR One Pro has a rugged design with rubbery edges for durability. According to FLIR, the One Pro can withstand drops of up to 1.8m on hard concrete. The FLIR One Pro has an accuracy of 0.1 degrees Celsius and a temperature range of -20 to 10 degrees Celsius. The device is covered by FLIR’s one year warranty on any defects in materials and workmanship.
The Competition
While you will find many other excellent devices in the market, the devices featured here made it to this list of the best thermal cameras based on their combination of features, resolution and convenience.
Other Frequently Asked Questions
Q: Can A Thermal Camera see through fog?
A: Since thermal cameras do not use visible light, they can see through fog, snow and light rain. However, the above atmospheric conditions might affect the distance that the device can see. Even in clear skies, its effective distance will be affected by inherent atmospheric absorption.
Q: Do thermal cameras work in thick smoke and fire?
A: Yes, thermal cameras will work effectively even when there are visual obscurants like smoke and dust. This is why they are commonly used by law enforcement officers and an emergency service crew to scan for victims and determine the extent of fires.
Q: Can a thermal camera see through walls?
A: No. Most walls are thick enough to keep a building insulated. This means that they are thick enough to insulate the heat from the other side of the wall from being detected by a thermal camera. Unless a wall is paper-thin, the device cannot see through it.
Q: Can a thermal camera see through glass?
A: No. If you take a thermal photo through glass, you will only get an image of yourself. This is because the camera will pick up the temperature being reflected off the glass, rather than the temperature of objects that are on the other side of the glass. Windows are designed to block IR rays, therefore IR rays from objects on the other side of the glass cannot be detected.
Q: Should I buy a qualitative or a quantitative thermal camera?
A: Qualitative thermal cameras allow you to view temperature differences but not the actual temperature readings. Quantitative thermal cameras, on the other hand, will give you accurate temperature readings. The best ones have built in software that allows you to view temperature differences as well as determine the actual temperature readings.
Wrapping It Up
If you are looking for the best device that will give you a combination of excellent build quality, durability, great convenience and exceptional performance, then you should really consider the FLIR E60, which topped as the best thermal camera in our list.
Jen Miller is a former electrical engineer and product specialist with more than 20 years of product design and testing experience. She has designed more than 200 products for Fortune 500 companies, in fields ranging from home appliances to sports gear and outdoor equipment. She founded Jen Reviews to share her knowledge and critical eye for what makes consumers tick, and adopts a strict no-BS approach to help the reader filter through the maze of products and marketing hype out there. She writes regularly and has been featured on Forbes, Fast Company, The Muse, The Huffington Post, Tiny Buddha and MindBodyGreen.