Observant gerbils will recall that we've been thinking for some time about using a thermal camera to try and glean some additional insights about the hardware we review. FLIR's One cameras have offered an accessible way into thermal imagers for some time, and we've gotten our hands on one of the second-generation One cameras today. This $250 add-on plugs into the Lightning port on iOS devices, turning them into thermal imagers with FLIR's companion iOS app. An Android version is also available.
The One works by combining a visible-light image with thermal data to provide a more detailed image than the relatively low-resolution thermal data alone would present. This technology, called "MSX," is the same special sauce the company uses in its more expensive discrete imagers.
In my informal testing on cats, people, computers, and refrigerators, the One has proven to be remarkably sensitive. It can show where people have been walking on carpeted and wood floors, and its spot-metering mode can show just how much of a temperature gradient exists between the hotter and colder parts of objects. Glossy metal things are the only objects the One has trouble with, although a built-in profile for glossy stuff can help. The company tells us that some glossy objects (like polished metal) are so reflective in the infrared spectrum that they give all thermal cameras fits, so this isn't a limitation that's unique to the One.
While $250 may seem like a lot to ask for an iPhone add-on, the FLIR One is far from a toy. It seems just as capable as FLIR's more expensive imagers, even if it's not as high-resolution as those devices. I do wish the temperature metering spot could be moved around the screen in real time, not just after an image is taken (although it's pretty neat that the FLIR One app can show temperatures anywhere in a thermal image after the fact). I also wish FLIR's image-processing algorithm didn't add artifacts to the already relatively low-resolution images from the camera. Screenshots of the FLIR One app actually look better than the images saved from the camera, strangely.
We'll be exploring possible uses for the FLIR One in our testing, especially in our case and cooling reviews. We're also open to suggestions for how we might use this gadget in our work. Let us know what sorts of information you might want to see us gather with this thing, and we'll see what we can do.
Updated 11/30/2015 with clarifications from FLIR regarding glossy objects and movement of the temperature metering spot.