Left to right: FLIR ONE, FLIR TG165, and FLIR E4
Unthinkable just a year ago, FLIR Systems now offers three thermal imaging devices for under $1000. All three have the same 80 x 60 resolution, and all are marketed as suitable for a wide variety of applications. Energy loss in buildings, dangerous electrical connections, overheating motors–can these bargain thermal cameras really do it all? We set out on a side by side comparison to get a better idea.
The three tools in contention are the FLIR E4 Thermal Camera, the FLIR ONE iPhone case, and the FLIR TG165 Imaging IR Thermometer. All are marked by the excellent production quality seen on other recent FLIR products, with smooth black rubberized plastic, good ergonomics, and a top notch fit and finish. With much in common, let’s take a closer look at the features of each unit.
Top: FLIR E4 without MSX
Bottom: FLIR E4 with MSX
FLIR E4 Thermal Camera, $995
- 80 x 60 resolution, 0.15 °C sensitivity, 45° lens
- Digital and thermal cameras
- Scene range temperature: –4 to 482 °F
- USB image download
- Removable battery and available charger
FLIR ONE for iPhone $349
- 80 x 60 resolution, 0.18 °C sensitivity, 50° lens
- Digital and thermal cameras
- Scene range temperature: 32 to 212 °F
- Flexible image download/transfer
- Records thermal video
FLIR TG165 Imaging IR Thermometer, $499
- 80 x 60 resolution, 0.15 °C sensitivity, 50° lens
- Thermal camera and infrared thermometer
- Scene range temperature: 32 to 260 °F
- Micro SD card or USB image download
- Target lasers for spot measurement
Imaging
Our imaging test pointed the three cameras at five different scenes to compare imaging clarity. Each image was taken from the same point, at the same distance, and within a few seconds of each other. Because the FLIR E4 and FLIR ONE feature MSX image enhancement, images are presented in this format. MSX combines the thermal image with data from the visible light image to give the scene more definition. But since the technology only works when there is enough visible light to take a digital image, the compressor group below is presented without MSX for reference. And although the images are three different sizes when downloaded, all below are limited to a maximum dimension of 220 pixels for the sake of clarity comparison.
Top: Area boxes and multiple spots are available on the E4.
Bottom: Spot temperature is the only option on the TG165.
Measurement
Since thermal cameras are used to measure temperature as well as image it, our comparison would not be complete without a few words about the temperature detection capabilities of each camera. Quoting the FLIR ONE manual, “The temperature indicated by the FLIR ONE is always a calculated estimate and never exact.” The FLIR ONE is obviously not a great choice for temperature measurement. Perhaps this is why the FLIR TG165 includes an infrared thermometer as well. It has similar imaging capabilities to the FLIR ONE, even sharing the same Lepton core, yet temperature measurement is handled by a separate (though integrated) IR thermometer. This thermometer is flanked by dual sighting lasers that help identify the approximate measurement spot size. With a 1.5% basic accuracy, the TG165 is also the most accurate of the group.
The FLIR E4 has a slightly smaller spot size ratio than the TG165, but also has a quoted basic accuracy of 2%. Better spot size but slightly less accuracy means the E4 and TG165 are probably a wash as to temperature measurement. As for in depth analysis of temperature, the FLIR E4 has one huge advantage over the other competitors: all images are stored with full radiometric data. To be sure, the FLIR ONE and TG165 store images, but more akin to a screenshot. Only the information currently on the screen is captured. On the E4, however, each point in the 4,800 pixel image can be mined for temperature later in the free FLIR Tools software. Users can place multiple spot meters in one image for the sake of comparison, then save and export the image for a report.
Final Thoughts
The FLIR TG165 won us over as the best thermometer of the bunch. It’s as good for measuring temperature as the E4 camera, yet also features targeting lasers, a very quick start up, and the convenience of SD card storage. As the images above suggest, it’s not great as a thermal camera, but it makes an excellent infrared thermometer. The FLIR ONE was the least expensive of the group, records thermal video, and produced the best images, at least on export. Yet while using the FLIR ONE, it was probably our least favorite. It’s hard to argue with a $349 thermal cameras, but the MSX doesn’t line up well on the live screen, and it generally felt like we could not see potential problems as well as with the E4. So it’s the E4 that takes home the victory as best thermal camera under $1000. The better on-screen picture, combined with the ability to analyze images later in FLIR Tools, crowns the FLIR E4 as victor. At least for now.
If you have thoughts or questions about any of these cameras, we would love to hear from you. Give us a call at (877) 273-2311, drop us a line at [email protected], or simply leave a comment below.
More Information
FLIR E4, $995 at Ivy Tools
FLIR TG165, $499 at Ivy Tools
Ivy Tools Blog 
Thanks for the review, I have buy the Flir One for using when i will and have recording and good picture quality and buy the FLIR TG165 for rugged dand the price/function of the device.
So i use the Phone for image quality and seeing what’s wrong and i use the TG165 for measuring.
Many said: buy an Flir E4, yes but flir E4 have not the same spec as the TG165 (laser spot for measuring is a great tool, you can point what you whant measur in the dark if you will. and for this price (TG165+ ONE + Iphone5) i reach the same price of the E4 (and i have two device and one Iphone, what else ^^)
The E4 is higer price, the reason (I think) is the Thermal imager is the same as the E8 but is locked at 80X60.
The problems, cannot find an affordable product with all i need “Video recording, Laser, MSX, etc…” yes have product with all this options, but… it cost an arm ^^ . So, i have all this functions with multiple device for a fraction of the price of an high end device.