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Flir One

FLIR One Thermal Imaging Camera for the iPhone is one very cool product. The $349 iPhone 5 and 5S add-on can see the heat signatures of people, places and things and, with proprietary software, converts the data into eye-popping, temperature-information-rich images that you can manipulate and share. You may struggle to explain why you’d need one, but there’s little question that you’ll probably want one.

FLIR System’s pricey technology represents another step in the continuing miniaturization of space-age technology. Like GPS systems before it, thermal imagers were once large, bulky, inordinately expensive and only for military and professionals. But with the invention of a roughly M&M-sized Lepton sensor, the sensing technology has finally made the leap to consumers. As one FLIR executive explained it, “We want to become the world’s sixth sense.”

See also: 8 Ways to Waterproof Your Gadgets

If you’ve ever seen the movie Predator, then you kind of understand the technology and how it looks. It’s a special sensor that sees the invisible heat signatures reflecting off surfaces. The gamut ranges from blue for cold to red and white for heat. The sensor doesn’t need light to do its work, so even in pitch black, the sensor will “see” the heat.

Test drive

I love Predator movies as much as the next pop-culture-obsessed nerd, so I jumped at the chance to take the FLIR One for a test drive.

Getting hot

To make thermal imaging work with an iPhone, FLIR Systems created a two-piece case that looks a bit like a cross between a Mophie battery and an add-on camera. In fact, that’s a pretty accurate description. FLIR One’s body includes its own battery and two sensors. One is the Lepton thermal imager, the other is a VGA camera.

That’s right, this study — and heavy (3.9 ouces) — add-on does not use the iPhone’s iSight 8-megapixel camera. Instead, it relies on a VGA one, which is only a few millimeters away from the thermal sensor. There’s good reason for this: The Lepton sensor shows the heat readings as blobs of color, but the VGA camera gives it context. The only way it can do that is by taking almost the exact same image. This allows the software to easily overlay a mostly transparent outline of the captured image on top of the thermal signature. The combined images shows you what’s generating or not generating heat. Had FLIR Systems used the iPhone’s camera, it would have been much, much harder to align the images.

Attaching the imager to the iPhone is easy: There’s a thin, traditional iPhone case that you can leave on your iPhone when not using the FLIR One. It has a hole on the back that reveals the Apple logo on the phone. That hole is also used to secure the thermal scanner which slips over the case. The scanner plugs into the iPhone’s lighting port and secures with a plastic nub that slips inside and then under the edge of the case hole. The whole thing holds together quite securely.

While the FLIR One has a hole for the phone’s audio jack, there’s no way to access the lighting port. At the bottom of the scanner is a micro USB port that will only charge the scanner. This isn’t a big deal since it’s unlikely you’ll have the scanner on your iPhone all the time.

As noted, the camera and scanner are on the back of the phone. Below them is a mechanical switch that slides a cover over both lenses and also serves to turn on and calibrate the scanner. The placement of this switch is not great. Any time you want to scan a new area, you usually have to recalibrate by holding the switch down for 3 seconds. Since pretty much the only way you can use FLIR One is by pointing the camera away from you, you’re usually reaching your fingers around to the switch to turn it on and calibrate. I often missed and put my finger in front of the lens. I hope future editions move this switch to the side of FLIR One.

Your first scan

One the left is a scan of the inside of a refrigerator. Note the ambient temp is 32 degrees Fahrenheit. On the right is a recently parked car. Image: Mashable, Lance Ulanoff

Scanning isn't hard, but takes, perhaps, a bit more patience than you’re used to from an iPhone accessory. You launch the free FLIR One app and move the switch to middle position, which uncovers the lenses and turns the scanner on. That startup can take a few seconds (up to 10). Next, you have to pull that same switch down to calibrate for the room or object you’re shooting (this more or less gives FLIR One a baseline, like white-balance for a camera). The device will vibrate and the phone will make a gentle tone once calibration is ready.

On the screen you’ll see an outlined, live image with colorful heat-signature information on top of it. If you select “Spot meter” from the menu, you’ll see a temperature reading (Fahrenheit or Celsius) for whatever is in near the center of the screen. If you start to move the FLIR One around a lot, it’ll probably ask you to recalibrate.

While FLIR One can let you see in the dark, there are some limitations. Since the VGA camera needs light, you’ll only see the color blobs in a completely dark environment. Settings, though, does give you access to the iPhone’s light – in case you want to illuminate the image and get better outline detail onscreen.

The app also lets you snap photos or videos and then share them out via email and social media.

Looks like a couple of people beamed into our weekly meeting. #startrek #FLIROne pic.twitter.com/YgHEvQ6pH0 — Lance Ulanoff (@LanceUlanoff) August 1, 2014

Other apps like Paint let you take a regular VGA photo and then, with your finger, paint in the heat signature for any part of it. It can create a pretty cool effect. There’s a panorama app to take panoramic heat-vision photos, and it works a lot like the iPhone’s own panoramic shot option (but takes a lot longer to process), another to take close-ups and one for time-lapse heat-signature photography. The last two did not come with my test iPhone, so I did not try them out.

One the left is the heat signature my hand left on a table and on the right is the heat signature my foot left on the floor. The only way you can see this stuff is with FLIR One or similar kind of thermal-scanning device. Image: Mashable, Lance Ulanoff

There are a lot of fun and silly things you can do with FLIR One. I took off my shoes and socks and padded around the house. FLIR one showed that I’d left a trail as if my feet were covered in orange ink. I was able to outline an image on a wall that only FLIR One could see. I also painted thermal-scanned people into VGA photos and shared them on social media and learned how to take a thermal selfie. I even got a picture of a squirrel.

What’s the temperature, Kenneth?

There’s no question that taking and sharing these kinds of images is fun, but not $349-worth of fun, which begs the question, why would you want this?

I decided to test out some of the scenarios FLIR Stems envisions for the device. I took thermal imagery of my plumbing, which thankfully, is working well. It’s showed red pipes where hot water was running and blue where cold water (or none) was running. If the drain had been clogged, I might have been able to see where the hot water stopped draining, but only if the clog was in the visible part of the pipe. FLIR Systems told me that because you can share images and they have the context of the VGA imagery, a plumber might be able to diagnose the problem my looking at the thermal scan.

One the left is a scan of my ceiling, which clearly shows which way the cool air is flowing and where the conduit is running in my ceiling. On the right is my plumbing. Image: Mashable, Lance Ulanoff

I took a lot of thermal images of the wiring in my office building and of my home wiring and wall chargers. At home, I noticed that the scanner showed one of my dimmable light switches as hot and wondered if that meant I should replace it. Many of my chargers generate considerable heat. I knew this intuitively, but could see it factually thanks to FLIR One.

On the left are wires and wall charges in my office. Notice the temp meter reading. On the right is conduit in my office building. Inside those pipes is some pretty warm wiring.

I took images outside my house where I could only faintly make out the bushes and trees. I noticed that all pavement and steps still glowed orange and red well after dusk, making it clear that they absorb heat all day and expel it at night. Parked cars shows still hot engines under the hood and glowing red tires.

See, but not through

One misconception about this kind of sensing technology is that it sees through things. It doesn’t, but if objects under the surface heat it more than others, then the outline of that hidden thing may appear. In the case of my house, FLIR One showed me faint, blue outlines of central air conduit running in my ceiling; filled with cool air, they lowered the temperature of the ceiling right below them and thus changed the heat signature for those areas.

On the left is a thermal scan of my plant before I watered it. On the right is how the dirt scanned after I cooled it off with some water. Image: Mashable, Lance Ulanoff

FLIR One didn’t always offer more information than I could glean with my naked eye. I was never able to see studs in my wall, which probably means the temperature between the wood, insulation and drywall is roughly the same.

FLIR Systems has published an SDK and is already working with over 100 developers to build new applications for FLIR One. In the meantime, this first iPhone Thermal Imaging Camera is a fun, albeit expensive tool that will appeal to DIYers, professionals who want to add thermal imaging technology to their tool belts — and gadget freaks like me.