Infrared cameras are very convenient for tracking insulation leaks in rooms, blockages in drains and hotspots in electrical installations. But such a camera can also offer the electronics engineer a solution to tracking down heat problems in circuits. In this article we compare two IR cameras from the American manufacturer Seek, which have sensors with a much higher resolution than those in other devices in the same price category.

We probably don't need to explain to most electronics engineers what such a thermal imaging camera does. In contrast to a normal camera, this one is not sensitive to the visible light spectrum, but is only sensitive to infrared radiation. And this radiation is a measure of the temperature of the objects that are observed. These temperatures are usually represented on the screen using different colours.

Large and small

Here we look at two products from Seek that are in very different price segments. On one side we have the semi-professional Seek ShotPro with a price tag of 850 Euro and on the other side there is the Seek Compact, a plug-in module for smartphones for some 300 Euro, which is available as an Android and an iPhone version. Nevertheless these two have one thing in common: They provide a very detailed image that shows an accurate distribution of the heat. To compare: an IR camera in the price category up to 1000 Euro has a sensor with at most 160x120 pixels, while the Seek ShotPro has 320x240 pixels. Even the relatively cheap Seek Compact already has a sensor with 206x156 pixels.

Seek ShotPro

Photo: Seek Thermal
The ShotPro is an standalone IR camera in the format of a smartphone. The entire housing is covered with a tough rubber covering and the thing looks like it could handle the odd bump. On the front is the lens with a lens cover, on the other side is a 3.5” touch screen. The camera can make a wireless connection to a PC using WiFi.

When touching the image on the screen, a bar appears at the top and bottom for the various settings. The top bar leads to the preference settings including the choice of temperature unit, setting the clock and the emissivity. The bottom bar gives access to the image settings. Here different colour patterns for the display of the image are available, which spot-temperatures are shown in the image and there is access to the stored screen shots.

A very important little icon is the “eye”, that offers the option of combining the thermal image with an image from the normal camera that is also built in. This results in a mixed image where it is much easier to see what you are measuring. You can adjust the amount that each image is displayed. There is also the option of shifting the IR image with respect to the visible one, so that they align with each other as accurately as possible. This feature can also be found on professional IR cameras.