Top 7 Best Thermal Imaging Cameras (2024 Review)

As a licensed home inspector, I have used thermal cameras numerous times to spot hidden problems during an inspection.

Thermal imaging cameras see the invisible world of infrared waves or 'heat' that is radiated by the environment.

These cameras can see hidden water leaks in a home, an approaching wild animal, electrical hotspots, missing insulation, and even human footsteps.

Below is a quick comparison of all our top products, and keep scrolling to read our buyer's guide!

What Is A Thermal Camera?

Thermal imaging cameras detect infrared radiation or heat in the environment and convert it into a visual picture or video.

Unlike normal cameras that detecting visual light in the 450 to 750 nanometer wavelength range, IR cameras use the 1500-nm to 10k+ wavelength range.

When you take a picture of a room using an infrared camera, it will show different colors or shades which represent the different temperatures of the environment.

The higher temperature objects will appear orange, yellow, and white while the lower temperature objects will appear blue or purple.

How Do Infrared Cameras Work?

Infrared cameras work by converting the heat (infrared radiation) in the environment into an electrical signal that is displayed visually on the screen — known as a thermogram.

The basics of the thermal imaging process is that the environment emits a heat signature which is known as infrared energy. It is essential to note that thermal cameras detect only the surface temperature, and not deep in the material.

The surface heat gets focused onto the camera sensor array which has a large number of different pixels. Each of these pixels produces an electrical signal that gets sent to the camera's processing chip.

And of the electrical signals than go through different calculations to come up with a temperature and corresponding color. This huge matrix of colors gets converted into a visual image onto the camera.

Read Also >> How To Interpret Thermal Images

What Are The Pros And Cons of Thermal Imagers?

Here are some of the advantages and drawbacks of thermal imagers:

How To Pick The Best Infrared Camera?

Here are a few important things to consider before buying a thermal camera:

1. Resolution

Probably the most important thermal imaging camera spec is the resolution or pixel count. Basically, the higher the resolution, the more thermal details you will see.

If you buy an IR camera with too low of a resolution, it will be difficult or impossible to pinpoint problems, and may be a waste of time. Buying a thermal sensing camera with too high of a resolution may be needlessly expensive. The basic minimum for most work applications, such as building inspections, energy audits, automotive, and electrical inspections — a good resolution is in the 160x120 range and higher.

Read Also: How Do Thermal Cameras Work?

2. Refresh Rate

Refresh rate represents the number of thermal images that are displayed in one second. Basically, thermal imagers with higher refresh rates have better quality imagery. A slow refresh rate will appear choppy but a high refresh rate will be smooth and seamless.

Most standard IR cameras are around 9-Hz which is equivalent to 9 frames per second. However, if you are using an IR camera to view moving objects outside, or from a far distance, a higher refresh rate of 30-hz or 50-hz is preferred. There are also a variety of import regulations regarding thermal cameras with refresh rates higher than 9-Hz.

3. Temperature Range

The temperature range is the maximum and minimum temperatures that it can measure. Most standard infrared cameras have a temperature range in the -15°F to 550°F range.

For average building inspections, a high temperature limit can be counterproductive and actually reduce image quality. 

But for some manufacturing and industrial applications, it is important to have a high temperature range exceeding 1500°F. A few of these areas include automotive, microelectronics, furnace/boiler installations, plastics, and mechanical testing.

4. Thermal Modes

There are a wide variety of heat sensitive camera modes that can make a big difference in a thermal inspection or application. Here are a few common modes:

• Thermal Blending is when the camera combines features of a visual image with the thermal image to show a "best of both worlds" picture
• Picture in picture is a mode that shows a thermal image and a visual image at the same time for comparison.
• MSX Technology is a proprietary thermal vision setting in FLIR cameras. This feature takes some of the border details of the visual image and overlays it onto the thermal image for enhanced imagery.
• Regular visual mode is standard with most cameras and it allows you to take normal visual pictures along with thermal pictures.
• Pure thermal is just the raw thermal image without anything else.
• Color alarms (isotherms) are when you set a temperature limit inside the camera, and it injects color into the 'hot' objects and keeps everything else on a grayscale.
• White hot mode is when the camera makes and 'hot' objects a white color and everything else is a dull gray.

5. Display

The actual display or screen that shows the thermal imagery can also make a big difference when choosing a thermal camera. If the display is too small or too poor quality, it doesn't matter how good the thermal camera is.

If the IR camera is attached to your phone, then the display will be your phone screen, but most thermal cameras have a separate display.

As with the thermal camera resolution, the higher the pixel count of the display, the better. Some displays also come with HD color quality while others are standard liquid crystal display (LCD) color screens.

6. WiFi Enabled

Some thermal cameras are able to connect to a phone or tablet. You may even be able to control the camera remotely such as with the Pulsar Helion 2. 

Having a WiFi connected thermal camera can be very useful to quickly share photos, videos with colleagues or customers. Through a WiFi connection, you may even be able to livestream the thermal feed to your phone or even to YouTube for a live audience.

7. Reporting And Editing Software

If you plan on using IR images or video in a professional setting, having a quality reporting and editing software is a must.

Most high end thermal sensing cameras will already come with a reporting software, but the quality of the application can vary.

Most FLIR cameras are able to use the FLIR Tools reporting software and they also have a cloud account known as FLIR Ignite that is used for uploading and storing thermal images.

8. Battery Life

Battery life can make a big difference when using a thermal camera. In my field of home inspections, if I am using a thermal camera for an energy audit and I run out of battery power, that is a big problem.

Most thermal imagers will have a wide range of battery life ranging from 1-2 hours on the low end and as long as 8+ hours.

Almost all thermal imagers have rechargeable batteries, so you just plug it in when you go home to recharge it. But if you can get a thermal camera with swappable batteries and an independent battery charger, then you can double or triple the battery life of the thermal camera.

How To Use A Thermal Imaging Camera For Home Inspections?

Whether you are a pro or the average homeowner, infrared cameras are incredibly useful tools to find air leaks, water leaks, and missing insulation.

Indoor Home Inspections

The most important thing to remember when using an IR camera is that there needs to be a temperature difference for the camera to detect anything. If the indoor temperature is the same as the outdoor temperature (also known as Delta T) then the camera will just be a blurry mess of the same color.

Ideally, users will want at least a 15-20 degree temperature difference. An easy way to achieve this effect is to max out the air conditioner or heater depending on the season. Once the indoor temp is distinctly different than outdoors, shut off the HVAC system and wait 15-minutes.

Checking For Air Leaks

If the main thing a pro or homeowner wants to do is look for air leaks, it is important to also create an air pressure difference in the home. This can be achieved by turning on all of the bathroom exhaust fans, range hoods, or any type of exterior ventilation system. The best method is to use blower door testing equipment, but most people don't have access to it.

Exterior Water Leaks

If homeowners are inspecting the exterior for water leaks, the best time is to wait for sunset or sunrise. This will allow a temperature gradient between the wet or moist areas of the wall or roof as compared to the surrounding materials. Water has a high thermal capacity and takes a lot of energy or time to change temperature.

What Are The Different Types of IR Cameras?

There are numerous 'form factors' or styles of thermal cameras on the market. Below are the some of the most common types:

Phone Attachment

Probably the least expensive camera type is the phone attachment thermal camera. These thermal cameras are plugged into your cell phone, and use the battery power of your phone. They are great for hobbyists, homeowners, and professionals who won't be using them for long periods of time. The portability and decent resolution is great for short term applications.

However, if you plan on using an infrared imager for a long period of time — such as for professional home energy audits — then a handheld 'trigger-style' camera is preferable.

Read Also >> What Are The Best iPhone Infrared Camera Attachments?

Handheld

The handheld style is highly portable and easy to use. However, these 'rectangular shaped' thermal cameras have their own battery supply so it won't drain your phone's battery life during use.

Also, these thermal imagers have their own screen which is usually larger than trigger type cameras. These thermal cameras avoid any issues connecting the camera to your phone and all of those types of problems. And again, these handheld imagers are also very nice for short periods of time, but for long and exhaustive applications, a trigger-style is still preferable.

Trigger Style

Trigger style infrared cameras are handheld devices that you hold with one hand as if your finger is on a trigger. When you actually press on the trigger with one finger it will take a thermal picture — without having to use your other hand. These devices are designed to be used for longer periods of time, and are easier and more ergonomic to use with one hand.

The downside of the trigger style is that the screens are usually smaller than phone-connected and handheld cameras.

If you plan on using thermal scanners extensively for home inspections or other professional uses — then these cameras are likely your best option. The trigger style camera is usually the most expensive.

Drone

Drone inspections are becoming frequently common across multiple industries including real estate, agriculture, wildlife management, rescue, and fire service. And now there are Drones with thermal technology (in addition to visual cameras) so the user can detect heat signatures of buildings, people, animals, and even crops.

Thermal sensing drones are great for rooftop home/building inspections and for areas that are inaccessible or dangerous. The drone can even be programmed with 'waypoints' so that it can perform an automated thermal inspection without user input.

Monocular

Thermal scopes or monoculars are designed for outdoor and long distance use. These heat sensing monoculars can detect heat signatures up to an astounding 2,000 yards or more. Even though the most popular use is in hunting and wildlife management, IR monoculars are also used heavily by researchers, inspectors, and analysts. 

Thermal imaging monoculars usually have very high refresh rates such as 30-Hz or more in order to see thermal objects on the move and from far distances. Traditional IR cameras are commonly less than 10-Hz.

Moisture Meter Combo

The moisture meter and infrared camera combo is a great device if your main purpose is moisture detection and water leaks. The infrared camera can quickly look over a large area of interest such as a basement.

And then using the thermal imagery, the user can quickly pinpoint areas of potentially high moisture and verify it with the moisture meter. Without a thermal camera, an inspector or homeowner would have to use the moisture meter blindly in numerous areas if there isn't any infrared heat detection.

What Are The Uses of Infrared Cameras?

Thermal cameras can be used in a wide variety of recreational and industrial applications. Here are a few of the most common ways to use them:

Home Inspections

I have used thermal imaging cameras on many of my home inspections. If I have a suspicion about water in a certain area, I can pull out my IR camera to get a quick overview of temperatures in the area to aid moisture detection.

I can also take a picture of the infrared environment and include it in my home inspection report. Even though I always use a moisture meter to confirm the presence of water or moisture—using a thermographic camera can also help greatly. 

Electrical Problems

Abnormal electrical connections can be easily spotted using a thermal imager. Loose wiring, electrical hot spots (or cold spots) and other electrical anomalies can be quickly detected using an IR camera. Especially with exposed electrical equipment, a homeowner or contractor may not want to get close to it. With a thermal camera, you can get a bird's eye view of equipment to do safe electrical inspections.

Checking House Insulation

Thermal cameras are great at finding missing or inadequate house insulation and air leaks. When inspecting an attic, it can be a nice way to get pictures of missing or inadequate insulation.

Attic insulation ideally should be several inches above the ceiling joists, but I frequently find that older homes have areas of only a few inches of insulation. But you can also check insulation on exterior walls too see if it is missing or sorely lacking.

Fire Service

Needless to say, thermal cameras are priceless during fires. Infrared cameras allow firefighters to see through thick smoke, keep track of how the fire is moving, get vital intelligence on how to fight the fire, and also find missing people.

Thermal scanners for firefighters need to be very rugged, and can be easily used without extensive training.

Law Enforcement

Law enforcement has been using thermal cameras for many years, and they are invaluable when trying to find a fleeing suspect in the dark.

And unlike night vision monoculars, thermal cameras don't need ambient light and can see humans in total darkness. These cameras can also help law enforcement to recover hidden evidence and to aid in search and rescue.