If you want to add thermal optics to your toolset or hunting arsenal but don’t want to spend thousands of dollars on a handheld machine or scope, the Xinfrared X2,at less than $400, is a fantastic midrange option that outperforms even more expensive solutions and offers a significant quality bump from the usual built-in smartphone thermal cameras.
The X2 is a tiny monocular camera with a two-times zoom and manual focus, which works over USB-C, though an iPhone-compatible model is also available. With a range of versatile mounting options, it can be useful in a variety of situations.
Xinfrared X2 Thermal Monocular
The Xinfrared X2 is a versatile and affordable thermal optics solution that outperforms built-in smartphone systems, offering higher resolution, manual focus, multiple mounting options, and a feature-rich app, making it an excellent choice for hunting, pest control, and other thermal imaging needs.
Mounting Options and Box Contents
You can use the X2 in one of three ways.
For the simplest setup, just pop it into the port on the bottom of your phone. That’s it. Just plug it in, launch the Thermal Eye X app, and you’re off. The package includes a carry case, so you can keep the sensor and USB-C cable safe when not in use. You should also keep the rubber lens cap on, and never point the sensor directly at the sun or naked flame.
But also included in the package is a grip holder, consisting of a comfortable grip, a smartphone mount, and a forward-facing mount for the X2, along with a USB-C extension cable. This is a very simple setup to use and likely the most common use case. It makes it much easier to take steady shots than awkwardly holding a smartphone.
Lastly, you can get an optional shell mount, both for protecting the module and mounting it directly to your rifle. The shell has a picatinny rail mount system and extension on the other side, so you don’t lose any precious rail if you have a laser or other accessories. Alternatively, you can use this same shell to mount it to a tripod with a small adapter. However, it isn’t a simple task to fit the X2 inside of the shell, with about eight small screws securing the monocular inside. You’ll need to thread another specially shaped cable, and the whole process is a bit fiddly. So once it’s inside, you won’t want to take it out again in a hurry. (Note, the bipod is not a part of the package)
The X2 sits securely inside this shell, and once constructed, you can attach your smartphone directly behind it, giving you a super simple close-range scope.
Overall, it’s an incredibly versatile system for handheld use or direct mounting for hunting and target acquisition. Unfortunately, my rifle is a bit sparse when it comes to rails, so I ended up with it mounted in a less than satisfactory manner underneath the barrel, which was pretty awkward to use in practice. But if you wanted to replace your scope entirely, then this is certainly a viable and a lot cheaper option than a full thermal scope.
That said, I will just say I found manual focusing once it was inside this pic rail shell to be really awkward. There’s a protective lip and sun shade that protrudes out the front, so have to put your fingers into the line of sight, which then, of course, means you can’t see how the focus is. This isn’t an issue when used inside the standard grip holder.
Weighing a mere 18.5g and measuring 23mm square by 23.8mm in depth with the lens, the X2 by itself doesn’t feature a display nor does it compute anything. It’s just a sensor that needs to be connected over USB-C, and you’ll need to download the Thermal Eye X app (the one with the evil eye-looking icon). That’s where the magic happens, and it won’t work with a standard camera app. You’ll need USB OTG functionality to be enabled for this to work, but any modern Android system should have this. While an iPhone-compatible model is available, we haven’t tested it.
The X2 features a thermal resolution of 256 x 192 pixels at a 50Hz frame rate. That doesn’t sound like much, but it is significantly higher than that available in smartphones. The Cat S62 pro, for instance, is 160 x 120, as is the Ulefone 18T, which I used for testing this. Most thermal smartphones are based on the FLIR Lepton 3.5 embeddable sensor, while the X2 system is proprietary.
Other than resolution, the most significant difference between the type of sensor embedded in thermal camera-equipped smartphones and the Infrared X2 is that smartphones will typically offer a hybrid view of the standard camera lens plus the thermal image processed together. The Thermal Eye app and X2 sensor only offer the thermal view. There’s no optical camera here; it is just an infrared view.
In practice, I found the resolution bump more than made up for it, providing a far better and easier-to-understand thermal view than I’d previously experienced with built-in smartphone sensors. However, I will just emphasize that it’s manual focus here; you need to twist the focus ring to dial in your target.
Thermal Eye X
The Thermal Eye X app does a lot of heavy lifting for the X2, with various image processing and enhancements, so let’s talk about the features offered.
As is standard, you get a wide choice of color palettes, enabling it to work stealthily with white hotspots, classic green nightvision mode, inverted black-hot for daytime use, as well as a slightly tweaked palette for bird spotting, or the more traditional iron red. So, there’s something to suit all situations you may find yourself using this for.
On top of that, you enable hotspot tracking, which automatically identifies and marks hotspots with a small red cross. However, this is only relative compared to the rest of the sensor view. Unlike the FLIR app, I found that the Thermal Eye X app doesn’t allow you to lock in a particular temperature range. The thermal view remains dynamic all the time showing relative temperature ranges, not absolute. This makes sense given the lack of hybrid camera overlay; you need the clarity of even small differences in temperature.
Another neat feature specifically for hunters is the ability to a customizable reticle. You can then adjust the color, type of crosshair, and the position, enabling you zero it directly for use as a quick scope. Once you’ve adjusted the reticle position, you can lock it off and close the adjustments. As long as the pic rail shell remains mounted, you can remove your phone and the reticle will remain accurately zeroed next time you plug in your phone.
You can also enable temperature labels for exact measurements, though I found that it added a significant amount of lag to the viewscreen, so isn’t appropriate for use in the field.
Comparisons to Embedded Thermal Imaging Smartphones
If you’re in the market for this device, you’ve probably also considered a smartphone equipped with thermal imaging as an alternative, so let’s look at some comparisons of the output you might expect from the smartphone option, and where its strength lies. For this, I used the Ulefone 18T, equipped with a Lepton 3.5 from FLIR. Other models using the same embedded sensor will offer much the same output.
In well-lit environments, the ability to merge a visual camera view with a thermal overlay (and featuring edge detection) can certainly be beneficial. The wider zoom of the smartphone sensor is also easier to work with in confined inspection work inside the home. However, th low resolution of the thermal element of this shot can be seen.
For nighttime use, there is no comparison. In poor lighting, the FLIR-equipped smartphone lacks any details, and the low thermal accuracy and resolution can be clearly seen without the crutch of a hybrid view. The following image was taken only by moonlight. You can make out the cold roof of the chicken hutch, and just about see something warm to the left.
The pure thermal view of the X2 combined with the zoom factor makes it the clear winner. The heat tracking feature correctly identified the chickens sat on top of the other chicken house—and you can even see another bird perched on the right of the picture, outside of the dome.
Once the camera sensor of the smartphone becomes useless in low light, the weakness of the embedded sensor approach becomes obvious.
Should You Buy the Xinfrared X2?
Overall, I found the quality of output from the X2 to be superb, and it’s going to prove immensely useful for pest control at night. The resolution and thermal accuracy are excellent, so even small differentials are perfectly visible. The minimum 2X magnification is great for use as a short-range rifle scope, but for those who use thermal imaging to inspect larger areas inside where you may not have that much room to maneuver, you may find yourself wanting something less zoomed; a standard 1X the same as a smartphone could prove to be more practical. On the other hand, if you’re inspecting smaller work areas such as circuit boards, you may appreciate the zoom level.
When mounted within the pic shell, the manual focus ring is awkward, but hopefully, you won’t need to focus too many times if you’re scoping out a particular target area. However, for run and gun mixed-distance use, it’s annoying, and you should use the handheld mount for that instead.
The X2 is a versatile infrared camera for a variety of use cases—but not all. Thanks to a versatile mounting system, it can be used handheld, or mounted. For the price, it offers outstanding quality and features. But if you value the convenience of an all-in-one smartphone system, with hybrid visuals and a lower resolution thermal overlay, you’ll find thermal imaging-equipped smartphones that cost not much more than the X2 by itself.
