Review: FLIR One Pro thermal imaging camera £399

Gadgets, Smartphones

Name: FLIR One Pro
Type: Thermal Imaging Camera
Specs: Click here for full specs
Price: £399.99

Oregon-based manufacturer Flir Systems has been producing a wide range of professional testing products for different markets including maritime, surveillance and defence industries for the last 40 years. It also offers a range of thermal imaging cameras for both the professional and high-end consumer, prosumer, markets. Here we look at its latest thermal camera, the FLIR One Pro. Designed for both the iPhone and the iPad, as well as now Android devices, it can detect heat loss and water leaks in your property and elsewhere. 


We’ve all seen those thermal images of places like the Houses of Parliament and Buckingham Palace (see below) which are designed to show just how much energy is wasted from various London  landmarks. DIY company B&Q conducted a survey of Britain’s draftiest buildings nearly five years ago and, perhaps not surprisingly, found the Queen’s 600 room residence was up there as one of the biggest losers of heat. 

Not that you have to live in a massive stately home to find out how much heat your property is or isn’t losing. Nor do you have to invest thousands of pounds in specialist equipment anymore. Thanks to US company Flir Systems it’s now possible to get a pretty good impression from an affordable thermal imaging camera that fits onto the lightning port of your iPhone or iPad (this is the same port that’s used for charging as well as for headphone use). Alternatively, the product is also now available for Android phones with the latest USB-C as well at the older Micro USB connector.

Available since 2014, it’s actually FLIR’s third version of the thermal imaging camera with the FLIR One still available from around £225. The key difference between the two devices is that FLIR One Pro features VividIR image processing to bring out thermal details and subtle temperature gradients that are needed by professionals. 

Set up is reasonable straightforward. Simply download the app from the App store here ( and switch the power on from the base of the unit. Provided with the camera is a tough black case while charging is via a USB-C cable which fits to the bottom of the unit.

As with the integrated iPhone camera there are various shooting options on board the FLIR One Pro. These include video, photo and time-lapse modes as well as a countdown timer. There’s also a torch option to illuminate the subject matter. In addition, there are also a number of other tools specifically for thermal imaging.

For example, by pressing the temperature meter you can monitor the temperature on various parts of the frame. This can be used for comparing, say, the temperature of the wall to the draftiest part of the window frame and can be viewed either as a rectangle or a square within the frame.

Alternatively by turning the camera around and putting in selfie mode you can see the temperature of your face if you want to! See picture below.

You can use the FLIR One Pro in selfie mode so you can see the varying temperatures of your face! This seems to show that I’ve got a cold nose

Other features include a facility to change the colour palette (including Arctic, Coldest, Contrast, Rainbow settings) and also to display the range of temperatures in the frame.

Either you can view an image in MSX mode, which blends the image detail from the colour camera with the thermal image to give you the best of both worlds or you can view in Normal Mode (ie. without thermal imaging switched on) if you just want to see the temperature of a particular area. See picture below. 

Normal viewing mode with the temperature ‘hotspot’ overlay

Detecting leaks

It’s all good fun and the images certainly look quite cool and psychedelic. But are there any practical uses for the FLIR One Pro? Well yes there are several although obviously it’s not a product that’s going to be relevant for everyone.

Certainly being able to measure the temperature in certain parts of a room is useful – if only to see how much heat you are losing from your property. For example I was shocked at the temperature difference between the windows and the walls. It’s also good to be able to see this represented as heatmap so you can see exactly where the heat losses are.

Nor is it just draughts that the FLIR One Pro can detect. It’s also possible to detect leaks from, say, your roof or from piping because a wet surface has a different thermal properties to a dry one.

Usefully FLIR have put together a whole host of short YouTube videos showing different applications here. These range from detecting hot water pipes in a wall to fixing leaky roofs as well as locating damp patches in your property. See video below as an example. 



Certainly the FLIR One Pro is an interesting product and for certain professionals such as heating engineers, builders and estate agents it could prove invaluable. For example, if you are going to knock a giant hole in a wall it’s certainly very useful to know where the hot water pipes are located! Similarly, if you are buying a new house it’s good to be able to spot a leak in the roof, perhaps caused by some loose tiles. The only real problem we experienced is that the camera is quite power hungry so you will need to keep charging it if you are planning to use regularly. 

Key Features:

CAMERA FEATURES & MODES                                                                                                                                                                                                                                                                                                                               Flir One Pro                                Flir One
Thermal Only
Visible Only
Video, Photo, Time-Lapse
Swipe To See Visible Image
MSX Distance (alignment)
Thermal Color Palettes 9 9
High / Low Gain Mode
IR Scale (Displayed on image, adjustable range)
Spot Meters (max.) 3 (movable) 1 (fixed)
Rectangular Region of Interest (max.) 3 (movable)
Circular Region of Interest (max.) 3 (movable)


Flir One Pro thermal imaging camera


Chris Price
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