Get an Idea of Which Thermal Imager is Right for You

With the ever-growing number of test-equipment available, inspectors who are looking to add thermal imaging into their services have a more difficult time than ever choosing a suitable thermal imaging camera. Manufacturers keep on dishing out new models while discontinuing older ones. And if that didn’t complicate things enough, the specifications and features listed by manufacturers can be difficult to understand for novice and inexperienced inspectors.

FLIR night vision

Source: Flir

If you start browsing through all the different FLIR night vision cameras, you’ll notice that based on price alone, not all of them are the same, even though they may have seemingly similar features and are made from the same manufacturer – FLIR. FLIR is an industry leader in thermal imaging cameras, and their products are second to none. Still, you have to choose the right FLIR thermal imaging camera for your application, otherwise, you’re just spending your money on something that won’t live up to your expectations and requirements.

Any experienced thermographer will tell you that there isn’t a single FLIR night vision camera that will suit every application. However, there are a few models that come close. Regardless, you need to define the intended purpose for the camera before you go shopping. This may seem like an easy task, but if you take a closer look, you’ll have trouble defining the many building inspection-related applications you’ll perform with the camera.

Thermal inspection requires knowledge of various different systems and disciplines associated with commercial and non-commercial buildings. But there are a few specifications that can point you towards a quality thermal imaging camera whether from FLIR or a different brand.

The resolution of the camera FLIR

Source: Toolguyd


The resolution of the camera should be as high as your money can afford. The image resolution and quality are determined by the FPA sensor of the camera, and unlike conventional digital cameras, FPA isn’t adjustable. That being said, look for a camera with a minimum of 320×240 FPA.

This will typically compare to VGA quality visible-light photos from the majority of digital cameras. Anything less than 320×240 FPA will result in pixelated and grainy images that won’t provide you with the information you need. Higher-resolution cameras provide more accurate and sharper thermal imaging. This specification alone will narrow down your ideal camera choice considerably.


The sensitivity of the thermal imaging camera refers to its ability to see the difference in heat and measure those differences. In other words, the sensitivity directly impacts the accuracy of the measurements, and it represents the smallest difference in temperature between two objects that the camera can discern.

The sensitivity of infrared cameras is measured in degrees Celsius, mK, or ideally, both. 0.10 degrees Celsius or 100mK are considered adequate, whereas 0.05 degrees Celsius or 50mK are considered great. Basically, the lower the sensitivity, the better.

The thermal imaging camera's temperature range

Source: Flir

Temperature Range

The thermal imaging camera’s temperature range is also quite important to consider. This indicates the maximum and minimum temperatures the camera can measure. For most building-related inspections, a -20 to 150 degrees Celsius temperature range is considered adequate. However, in some applications, you’ll want a camera that can measure up to 250 degrees Celsius or more. Basically, you should consider the temperatures you’ll frequently be encountering in your inspections.

Screen Size & Refresh Rate

Accurately interpreting the information displayed from the readings can be difficult with a small screen, let alone with a poor screen resolution. A larger screen can help you make the right call while on the field instead of having to wait to upload your images to a laptop or another device. The screen display shouldn’t be smaller than 6-7 centimetres. You’ll also find models with 12-15 centimetres or more, and of course, they’ll make it even easier for you to see the results and convey them to your clients.

Another important feature is the refresh rate. 60Hz are commonly available, and they’re the same refresh rates found on most digital video recorders. A 60Hz display rate will give you almost live-like feeds when you’re moving the camera. Slower refresh rates, on the other hand, will make it seem like there’s a delay when you’re moving the camera and it will take some time for the camera to properly focus where you point it.


As you can probably tell by now, infrared cameras come in a wide range of shapes and sizes. They’ve become more portable and efficient than ever. Quality modern cameras should be easy to use and manipulate around objects and corners, and you should be able to use them at odd angles. Some models feature straightforward point and shoot type cameras, while others that come with lens systems that rotate or tilt. Every style has its own advantages and disadvantages, and it all comes down to personal preference.

Camera weight is also something worth considering, as you may have to use it for extended time periods. A lighter model is always preferable, as it reduces the physical strain that comes with long inspections.

Twenty years from now you will be more disappointed by the things that you didn’t do than by the ones you did do.