This is the TS004 Thermal Monocular:

Let's put it through its paces!

Hardware

This is a chunky bit of kit and fits nicely in the hand. It's well weighted and feels sturdy.

The rubber seal fits tightly around your eye and is excellent at keeping light out. The screen is set a little way back, so is easy to focus on. Taking a photo of the screen itself was a little tricky - here's what you can expect to see when using the settings menu:

The focus knob near the viewfinder is a little stiff, but it turns silently.

There's a rubber lens cover which is attached and can be easily tucked away next to the standard tripod mount. It comes with a lanyard strap, so you're unlikely to drop it. The buttons are well spaced and respond quickly.

The USB-C port has a rubber flap to keep out moisture.

OK, let's take some snaps!

Photos

Photo quality is pretty good - although limited by the technology behind the thermal sensor. The TS004 has a thermal resolution of 256x192 and images are upscaled to 640x480.

One thing to note, the user-interface is burned in to the photos. So if you want the battery display on screen, it will also appear on the photo. Similarly, things like the range-finder appear in the image.

There's a reasonable AI built in. It is designed to tell you what sort of wildlife you've spotted. In some cases, it is pretty accurate! A woman walked by me while I was looking for wildlife - here's her photo:

Nifty!

Here's a photo of a fox:

There are remarkably few wild boars in London!

Video

Video is also 640x480. It is a very smooth 42.187 FPS and a rather chunky 2,162 Kbps - leading to a file size of around 20MB per minute. With around 30GB of in-built storage, that shouldn't be a problem though. There's no audio available and, just like the photos, the UI is burned into the picture.

Here are a couple of sample videos I shot. In them, I cycle through the colour modes and zoom levels.

First, an urban fox foraging in London:

Second, some parakeets flapping around a tree:

I'm impressed with the smoothness of the video and how well it picks up heat even from relatively far away.

Linux

Bizarrely, on Linux it shows up as 1d6b:0101 Linux Foundation Audio Gadget. It presents as a standard USB drive and you can easily copy files to and from it. 100% compatibility!

You can't use it as a WebCam - for anything more complicated than copying files, you need to use the official app.

App

The TopInfrared App for Android is reasonably good. It connects to the camera via WiFi and offers some useful features. Most impressively, it live-streams the camera's view to your phone.

From there you can take photos or videos and have them saved straight onto your device. Handy if you've set the camera up outside and want to view it from somewhere warmer.

Frustratingly, it isn't possible to set all the options on the camera using the app. For that you need to go back to the menu on the camera - which is slightly laborious.

The app isn't mandatory for most operations - thankfully - but it is the only way to set the time and date on the monocular. You will also need it if there are any firmware updates.

If you don't need the app, you can turn off the WiFi to save some battery life.

Drawbacks

The device works - and is great for wildlife spotting - but there are a few little niggles. I've fed these back to the manufacturer and have included their responses.

• There's no EXIF in the photos, or any way to get thermal data out of the images.

  • "These products focus on image clarity, high sensitivity, and low latency. For example, temperature-measurement thermal cameras typically run at 25 Hz, while the TS004 operates at 50 Hz for smoother viewing. Devices that include EXIF temperature data, raw thermal export, and analytical tools are measurement-focused thermal cameras, which are based on a different design and use case."

• As mentioned, having the UI burned into the photos and videos is slightly annoying.

  • You can turn off the UI elements on screen which stops them appearing in the photo.

• The range-finder only works in yards and, while seemingly accurate, isn't overly helpful to those of us who think in metric!

  • "Unit switching will be available in the March firmware update"

• Once you sync the time with the monocular, all the filenames are timestamped like 2026_02_09_12345678 but it appears to be hardwired to Hong Kong Time (UTC+8) - so your dates and times might be a little out.

  • "We will investigate it and see if it can be implemented in a future update"

• The AI detection feature doesn't seem particularly tuned for the UK.

  • "Due to hardware limitations, the current recognition is relatively basic, so there is limited room for significant improvement"

In terms of hardware limitations, there's no GPS. I would expect a device in this price-range to have basic GPS functionality to allow you to easily tag photos.

None of these are show-stoppers, but for a device this expensive they are an annoyance.

Price

OK, so you want to spot birds in trees and wild boars foraging in the forest - what'll this cost you?

Close to £400 - you can use code TERENCE15 for a 15% discount until 16 February 2026.

The price of thermal imaging equipment is high and this is a fairly niche form-factor. It is easy to use, has a great range, and the rubber eyepiece is much nicer than staring at a bright phone screen. The battery life is excellent and you certainly can't complain about the generous storage space.

There are some minor irritations as discussed above, but it is an exceptional bit of kit if you like to explore the environment. Are you going to spot any cryptids with it? Who knows! But you'll have lots of fun discovering the natural world around you.

Topdon have sent me a mid-point model to review. It's relatively cheap for a thermal imaging product - only £140 on Amazon. I think the sensor is made by Raytrontek. But is it any good?

While it has a bunch of useful features, there's no video recording and it doesn't work with Linux. Other than that, it's fine.

The Good Points

It seems broadly accurate. Point it at a bunch of things and you can see their temperature. Here's my beautiful face:

That's the actual size of the file. Their marketing bumph says:

TISR (Thermal Image Super Resolution) uses AI algorithms to add simulated pixels between existing ones, enhancing low-resolution thermal images into clearer, high-resolution visuals.

Let's be honest, there's no AI in a device this cheap. There are various complex rules about Infrared cameras and their resolution. These images are fairly low quality - but more than good enough to help you spot a leak or work out if something is too hot.

Quick start up is great. It is ready to go a few seconds after pushing the power button.

The trigger grip is comfortable and responsive - it makes the whole device very "point-and-shoot".

There's a standard tripod screw fitting at the bottom.

The camera is at a slight angle from the grip, so you'll need a tripod with a tiltable mount. You also get an lanyard in the box, which is easily secured to the device.

There's a file-browser built in - which also lets you delete photos.

USB-C for charging and data transfer. Same as all your other gadgets, I hope!

But…

Resolution is low. That's normal for these sorts of cameras, but because the output is only 240x320 it means the on-screen text is cramped and looks pretty poor.

The interface is basic. It doesn't look brilliant, but it is usable.

Setting the time, for example, is a bit of a pain:

Once you've gone in to set the time and other basic settings, you'll probably never go back to it.

Storage space is low - only 480MB. To be fair, images are under 100KB, so you could store several thousand before you hit a problem.

There's no video recording. That's a bit of an arse if you want to see how something heats over time.

You can't extract temperature information from the images. There's no EXIF, no standard metadata, just whatever is printed over the photo. Again, good enough for a quick check but, given the small viewable size of the images, it would have been nice to print the information separately. You can remove some of the on-screen elements from the image. Here's my air-conditioning unit:

The rubber flap protecting the charging port makes it difficult to insert the cable.

Because the port is on the top of the device, it's sensible to protect it from debris, but it is a bit fiddly to use.

Linux Information

This shows up as 3474:0020 Raysentek Co.,Ltd Raysentek MTP. In theory, it should just show up as a device in your file explorer. But it doesn't work.

I couldn't detect anything with mtp-device - it didn't show up. dmesg showed the dreaded device not accepting address 53, error -71 which, I think, indicates a power problem.

lsusb -v shows it claims to support Picture Transfer Protocol.

I reset the device, formatted its memory, used different cables and ports, restarted everything, I even tried it on my Android phone. Nothing.

Which rather puts a damp squib on things. If you can't get the images off the device, you're stuck peering at them on a tiny screen with no way to share them with others.

It will work with Windows. I tried it in VirtualBox and it showed up - albeit with the name "Cobra".

Verdict

Fora quick and dirty inspection, this is a perfectly fine little device. Point it at a thing and see how hot it is. Squeeze the trigger and capture the image for later viewing.

The tripod attachment is handy and there are enough settings hidden away for you to set it up for your own personal needs.

The buttons feel a bit crap and flap gets in the way of the USB-C charging port.

It doesn't work with Linux or Android - I wasn't able to test it on a Mac - so make sure you have Windows available for getting the images off it.

This is one of the cheapest stand-alone thermal cameras you can buy. Necessarily, there are compromises involved with things at this price-point. The camera works (albeit not with Linux) and is a great way to get started with Infrared photography and monitoring.

Let's get this unboxed and working!

Demo

Photos

The photos are stored as JPGs which can be read by any normal graphics program. They also contain the thermal metadata which you can extract with specialist tools.

Here's the full photo taken with the camera. It shows the interior of an office with some computer equipment on a shelf.

You aren't going to get high-resolution photos out of this - 256x192 is what the thermal sensor provides. That's overlayed on a graphic.

It includes different filters so you can see just the thermals, the real image, or a mix of the two.

Because the optical camera is quite some distance from the thermal camera, it doesn't cope well with close ups - as you can see. Luckily, this can be adjusted in the UI by pressing the up and down keys.

Videos

As well as static shots, it will take video - 240x320 resolution and 25fps - well, ish. It looks a bit jerkier than that to me. But it is good enough to see what's going on.

In this video, I've recorded a bath filling up. Towards the end, I've changed the settings so it shows more of the real-colour video with the heat overlayed.

Filesize is about 1.5MB per minute - I've recompressed it for upload. I couldn't see any specific thermal metadata in the video.

Linux

Amusingly, it shows up as 1f3a:1000 Allwinner Technology Prestigio PER3464B ebook reader (Mass storage mode). Nevertheless, the 30GB volume was mountable and had an IMGS/ directory full of JPGs.

There is a Windows app, which I was able to run in PlayOnLinux. It offers a few features, such as being able to change the colour scheme of the photo, and pick out specific temperature points.

What's Great

The integrated lens-cap is is a thoughtful touch. As is the hand-strap and included padded case.

The trigger action feels great and is instantly responsive. There are a bunch of menu options if you like to fiddle with things.

Oh, and it is USB-C! So it will take the same charging and data transfer cable as all your other gadgets.

Overall, a nice package.

Downsides

The button layout is a little odd. The buttons feel nice and are responsive. But I would have expected the "Enter" button to be in the centre of the directional buttons.

It is a little slow booting up - but then, this isn't designed for quick action shots.

After taking a photo or a video, it asks if you want to save it every time. That's a little annoying. There's 30GB of storage and photos are only about 300KB - so it should be good for about 100,000 photos.

The videos are recorded without sound. A cheap microphone would make it easy to narrate what's going on in a shot.

Weirdly, the bundled app doesn't work on videos.

There's no expandable storage - the 30GB is plenty, but sometimes it is easier to shove an SD card into a computer.

Finally, there's no mounting point. Other cameras I've tried have a connector so they can be attached to a tripod. This is strictly hand-held only.

Verdict

This costs £200 - £250 depending on whether the algorithm likes you. Astonishingly, that's cheap for a thermal camera of this quality!

If you're into DIY, or you want to check the thermal efficiency of your home, or you just want to see how hot things are - this is a useful bit of kit. It's sturdy and well built. Dragging images and videos off it is a breeze - even if you don't use the official app.

The interface isn't the greatest thing in the world. But all you need to do is point and click. It's the sort of thing that's unexpectedly handy around the house with all sorts of tasks - from checking if the radiators are balanced, to seeing if a hidden plug is spewing heat.

£200ish isn't cheap cheap. But it is cheap enough that most geeks should have something like this. Also worth buying for community groups who want to check for heat leaks in their properties.

If you are happy with the slight user-interface oddities, and don't need a tripod mount, this is an excellent gadget.

Readers of this blog can use coupon code TEB15 for an exclusive 15% discount.

If you're American and would prefer to buy from Amazon.com, get 10% off with code E5W6NW8V until 2024-06-30 https://www.amazon.com/dp/B0CB7Q6J79

It's smaller than a normal USB stick and barely weighs anything. Shove the USB-C protrusion into your Android phone, launch the app, and... nope - that's it! Pretty much instantly plug and play.

There's also a reasonably long USB-C extension cable, so you can poke the camera in small places without needing to get your phone up close to something hot. But, if you do want to get close, the magnetic cover acts as a macro lens. Perfect for seeing which capacitor on your motherboard is about to blow!

Image Quality

The IR lens is only 256x192. It doesn't sound like a lot, but that's quite high spec for these sort of consumer devices. Everything is upscaled - and there's an overlay to show you the temperatures. Here's my face - what a cold nose!

There's no IR EXIF, sadly, but you do get GPS.

Video

The video is upscaled to 1080x1440 - which allows for the information overlay to be a sensible size. Frame rate is about 11fps - but we're not going for cinematic quality here! Codec is h264 but fairly uncompressed.

There doesn't seem to be a way to get rid of the InfiRay watermark - but perhaps it is burried in the app settings somewhere?

App

The Android app is spartan, but functional. You can fiddle around with the camera's colour pallets, play with some image and video quality settings, and record video.

It's also possible to show your phone's camera simultaneously with the thermal image - so you can get an idea of what you're seeing.

Linux Nerds

The camera shows up as 0bda:5830 Realtek Semiconductor Corp. USB Camera and is automatically recognised as a USB camera.

The only issue is with the way it presents itself. Opening up Google Meet shows the image split like this:

No idea what's going on there! But it should be easy enough to stream from the camera and post-process it.

Price

Now, here's the rub. What with the global chip shortages and the need for IR sensors in military equipment, the price of these devices is unfairly high.

The price on Amazon is around £220 - use the code terence12 to get a discount. That's a chunk of change! But these cameras are useful if you want to check for leaks, or dodgy insulation, or whether your computer is overheating.

You can also buy from the official website.

I've reviewed several IR cameras. The P2 Pro is a great gadget. It's small, the app doesn't suck, and it seems pretty accurate.

It's a bargain if a group of you are buying it for a hack-lab.

I have a new Thermal Imaging camera. It automatically saves photos in two formats. The first is a standard JPEG with false colours and metadata superimposed.

The second is a .irg file which can only be opened by the Windows-only software which comes with the camera.

Judging from what that software shows, the .irg contains a raw thermal image and separate metadata. That makes it more useful for analysis.

What I know (not much!)

Here's what I can find out about this undocumented file format.

Every .irg file is exactly 131,080 bytes. I presume that means the image is stored as an uncompressed array of pixels - the thermal sensor is only 256x192. And I also guess that it has fixed length fields for metadata?

Each file has a different MD5 hash - so these are unique.

I couldn't identify the images with the standard Linux tools of identify, strings, file, or exiftool. Thermal Imaging tools like ThermImageJ weren't able to read them.

Running binwalk showed that there was a JPEG at 0x1FAC0 until the end of the file. Each .irg had exactly the same JPEG attached:

An unexciting, 180x240, 1,352 byte, lump of green. There's no exif in it.

A hexdump shows that all the .irg files start with the same header:

0000000 0bb0 0080 a8c0 0000 00f0 00b4 c000 00a8
0000010 f000 b400 0000 a8c0 0000 00f0 00b4 251c
0000020 0000 7e7c 002d 7e7c 002d 1388 0000 0fa0
0000030 0000 2710 0000 0000 0000 2710 0000 0000
0000040 0000 0000 0000 0004 0000 0002 0000 0000
0000050 0000 0000 0000 0000 0000 0000 0000 0000

That doesn't look like any file signature I recognise.

The metadata on the software's PDF manual showed it was written by Infiray. They don't have any details on their site and haven't responded to my emails.

My knowledge of comparing hexdumps and trying to interpret them is lacking. It looks to me like there is a bunch of regular data in there, but I wasn't able to make head nor tale of it.

There are some articles about decoding these sorts of files but I wasn't able to apply that knowledge.

Your turn

Well gang, I'm stumped! Here is a zip with 5 JPEGs and their corresponding 5 .irg files.

If you can decipher how they work, or get me any closer to an open source viewer, please let me know!

Progress

James has a quick scrap of Python to extract the black and white image.

I think that's just from the visual sensor, rather than the thermal sensor - but it's a start!

Further Update!

Phil has completely reverse engineered it!

I've just been sent the TopDon TC004 handheld thermal camera to review. It's a chunky beast of a device. About the same size as a large barcode scanner - and pretty weighty. It promises superb thermal imaging, video recording, and a host of useful features. But how does it do? And, more importantly, how well does it work with Linux?

Overview

The UI is simple. Squeeze the trigger and it takes a photo. Hold the trigger and it shoots video.

The trigger has a satisfying action. The other UI buttons are a bit rubbery but do the job well enough.

There are bunch of options to fiddle with - you can change the colour scheme for the photos and a few other odds and sods.

It dumps out JPG images, and H264 video. It also produces .irg files which appear to be a proprietary file format containing the infrared data - more on that later.

There's a built-in torch, which is handy if you're looking in darkened corners. There's also a screw port for a standard tripod.

All-in-all, it's a great feeling product with a bunch of useful features.

Gallery

Here's a sample video. You can see that it can detect the residual warmth of my feet on the floor:

Here's Liz getting some food out of the freezer. I think it's impressive how much detail it has captured across the range:

Our gas boiler, with pipes emanating.

How much hotter is an Amazon Alexa than the ambient temperature of our kitchen? Quite a bit!

And, the obligatory selfie. Possibly useful for seeing if someone has an elevated temperature.

Linux Info

I was delighted that this was the epitome of plug-and-play on Linux.

In USB Mass Storage mode, it showed up as 0525:a4a5 Netchip Technology, Inc. Linux-USB File-backed Storage Gadget and exposed a single DCIM folder which was full of JPGs.

In the settings menu is the option to turn it into a glorified webcam. I flicked it on, rebooted, plugged in and... it just worked! Showed up as 12d1:0000 Huawei Technologies Co., Ltd. MCamera

I fired up Google Meet and was able to join my boring conference calls in exciting heat-vision.

Software

There's a Windows-only piece of software for managing the camera called TD View. Using PlayOnLinux it installs and runs. Although, on startup, it will all be in Chinese.

Once that was changed to English, it becomes fairly obvious how to use it. Point it at a folder full of images and you get a gallery

I wasn't able to get the software talking directly to the camera - but it can read and manipulate the weird .irg files.

Using the software is the only way to get the images without a superimposed timestamp on them.

Price

Brace yourself... It's four hundred quid! If you're going to be using it constantly, I dare say that's a pretty good price. Spending every day looking for leaks, hot wires, and the like will see it pay for itself quickly. If you're a DIYer... well, you've probably got more expensive gadgets that you rarely use, right?!

It's the sort of thing that would be a great present for a community or gadget library. Being able to show every house on your street where they would benefit from insulation would be excellent value for money.

If you're a gadget freak like me, you'll enjoy the novelty of having yet-another USB-C gadget which will be used for an as-yet-undetermined project.

Downsides

Other than the price, there's not a lot to complain about. The UI is passable, with only a few weird translations.

There are a few technical glitches. Videos as saved with a file extension of .h264 - they're MP4 files but might not be detected as such. The video resolution is reported as 1280x720, so appears distorted.

There's no EXIF on the images. Nor is their any GPS. It would be nice if the video recorded sound - but it is silent. The frame rate is low - but you're not exactly making IMAX videos on this.

It's a bit annoying that photos are stamped with the battery level and date / time. It's possible to get the raw images from the .irg files using their software - but I wish a more standard file format had been used.

The weight isn't an issue when holding the device - but becomes a problem when using a lightweight tripod. Because of the angle of the shaft, the tripod head needs to be tilted forwards - which puts it at risk of toppling.

Verdict

As a camera and a tool, it is stunning. Well put together, solid, and chock full of useful features. Battery life is also brilliant.

The proprietary file format and weird software are a bit annoying but can be worked around.

Yes, it costs a fare whack, but it's a useful gadget especially if you want to see how thermally efficient your house is.

Thanks to TopDon for the review unit.

The Seek Thermal is a curious beast. While you can buy Android phones with built in thermal cameras, and dedicated devices, this is an add-on. Plug it into your existing phone, download an app, and off you go. In theory!

Here's a quick selfie!

Why a selfie?

It's backwards!

If you get the USB-C version, you can plug the camera in for either direction. Great! If you have the micro-USB version, you're stuck in selfie mode. Boo!

Quite why Seek decided to put the connector on this way, I have no idea. There are only a handful of phones where this orientation makes sense.

Improvise Adapt Overcome!

I picked up a cheap OTG adapter. Note: make sure that it is a sync or OTG adapter. Otherwise the camera won't work.

A bit ramshackle, but it works!

Here's a photo of my wife drinking a hot cup of tea.

Photos are 960x1280 resolution and about 600KB - so won't take up too much space on your phone. Weirdly, images are stored in /Pictures/Seek Thermal/ rather than the more normal /DCIM/ folder.

Accuracy

Here's a photo of a mug of boiled water and an ice-cube tray.

That's pretty good! To be honest, I'm not using this for precise measurements - I'm looking for thermal disparities. You can set it to Celsius, Fahrenheit, and Kelvin.

App

The Seek Thermal app is a little basic. It works, but isn't great to look at. It mostly links to lots of videos on how to use it.

You will need to set your device to USB OTG mode - and give the app permission to talk to the camera.

You can choose a variety of overlays - including max and min temperature. You can also add location metadata to the photos and, for some reason, the camera serial number.

If you don't like the default colour palette, that can also be changed.

Usage

Again, basic but workable. The camera makes a constant clicking noise while in operation. Apparently that's normal - but sounds a bit weird. You're unlikely to take surreptitious photos with it. Their FAQ says:

There’s no need to worry, this is simply the noise your camera makes while you are shifting it between different fields of view. The noise you are hearing is the camera focusing and calibrating the image to achieve the highest resolution possible.

There is a manual focus wheel on the camera. It seems to adjust the picture, but I'm not sure how yet.

Video

It also does video.

Apparently, the frame rate is restricted to 15fps due to international munitions sanctions...!

Compare and Contrast

This is a cheap camera. Here's what an expensive FLIR camera produces:

Terence Eden is on Mastodon

@edent

Thermal Imaging Selfie!
Have serious professionals here measuring the house's heat flow. Have borrowed their Android (!) FLIR camera. pic.x.com/Q1CRyeTyvI

---

That's much clearer - but about twice the price. Speaking of which...

Cost

About £260 for the micro-USB version. If you want higher resolution, expect to pay significantly more.

Youch!

Verdict

This is a bit of a luxury purchase. If you want to see where your house is losing heat, or if there's a hot wire in your walls, or if your radiators are heating up - it's a cool gadget. The app is a bit basic, but works.

Being able to tell the body temperature of strangers leads to some interesting privacy questions.

Would I pay full price for this? No. But if you can pick one up second hand, or borrow one from a hackspace, they're fun and useful. As winter draws in, I'm going to be seeing just how good our home is at retaining heat.

Thanks

Many thanks to Brie for the generous gift.