Cheap Thermal Camera Fits The Bill

August 10, 2025 by Al Williams 14 Comments

If you want to save a little money on a thermal camera, or if you just enjoy making your own, you should have a look at [Evan Yu’s] GitHub repository, which has a well thought out project built around the MLX90640 and an ESP32. The cost is well under $100. You can watch it do its thing in the video below.

There’s a PCB layout, a 3D-printed case, and — of course — all the firmware files. The code uses the Arduino IDE and libraries. It leverages off-the-shelf libraries for the display and the image sensor.

Continue reading “Cheap Thermal Camera Fits The Bill” →

Light Transport And Constructing Images From A Projector’s Point Of View

August 7, 2025 by Lewin Day 6 Comments

Imagine you have a projector pointing at a scene, which you’re photographing with a camera aimed from a different point. Using the techniques of modelling light transport, [okooptics] has shown us how you can capture an image from the projector’s point of view, instead of the camera—and even synthetically light the scene however you might like.

The test scene used for the explanation of the work.

The concept involves capturing data regarding how light is transported from the projector to the scene. This could be achieved by lighting one pixel of the projector at a time while capturing an image with the camera. However, even for a low-resolution projector, of say 256×256 pixels, this would require capturing 65536 individual images, and take a very long time. Instead, [okooptics] explains how the same task can be achieved by using binary coded images with the projector, which allow the same data to be captured using just seventeen exposures.

Once armed with this light transport data, it’s possible to do wild tricks. You can synthetically light the scene, as if the projector were displaying any novel lighting pattern of your choice. You can also construct a simulated photo taken from the projector’s perspective, and even do some rudimentary depth reconstruction. [okooptics] explains this tricky subject well, using visual demonstrations to indicate how it all works.

The work was inspired by the “Dual Photography” paper published at SIGGRAPH some time ago, a conference that continues to produce outrageously interesting work to this day.

Continue reading “Light Transport And Constructing Images From A Projector’s Point Of View” →

Why Cheap Digital Microscopes Are Pretty Terrible

August 3, 2025 by Maya Posch 41 Comments

The depth of field you get with a cheap Tomlov DM9 digital microscope. Pictured is the tip of a ballpoint. (Credit: Outdoors55, YouTube)

We have all seen those cheap digital microscopes, whether in USB format or with its own screen, all of them promising super-clear images of everything from butterfly wings to electronics at amazing magnification levels. In response to this, we have to paraphrase The Simpsons: in this Universe, we obey the laws of physics. This applies doubly so for image sensors and optics, which is where fundamental physics can only be dodged so far by heavy post-processing. In a recent video, the [Outdoors55] YouTube channel goes over these exact details, comparing a Tomlov DM9 digital microscope from Amazon to a quality macro lens on an APS-C format Sony Alpha a6400.

First of all, the magnification levels listed are effectively meaningless, as you are comparing a very tiny image sensor to something like an APS-C sensor, which itself is smaller than a full-frame sensor (i.e., 35 mm). As demonstrated in the video, the much larger sensor already gives you the ability to see many more details even before cranking the optical zoom levels up to something like 5 times, never mind the 1,500x claimed for the DM9.

On the optics side, the lack of significant depth of field is problematic. Although the workarounds suggested in the video work, such as focus stacking and diffusing the light projected onto the subject, it is essential to be aware of the limitations of these microscopes. That said, since we’re comparing a $150 digital microscope with a $1,500 Sony digital camera with macro lens, there’s some leeway here to say that the former will be ‘good enough’ for many tasks, but so might a simple jeweler’s loupe for even less.

There are some reasonable hobby-grade USB microscopes. There are also some hard-to-use toys.

Continue reading “Why Cheap Digital Microscopes Are Pretty Terrible” →

Double The Sensors, Double The Fun, With 2-in-1 Panoramic Camera

July 31, 2025 by Tyler August 20 Comments

When film all came in rolls, it was fairly easy to play with the frame of the image. Companies like Hasselblad (and many others) made camera backs that would expose longer strips of 35 mm film to create stunning panoramic images in one single shot. [snappiness] wanted to bring that style of camera into the digital age, and ended up with a 2-in-1 Sony-based frankencamera.

Sensors just aren’t readily available in the wide aspect ratio [snappiness] was looking for, and even if they were, bare sensors are hugely expensive compared to consumer cameras. Lacking the budget for high-res scientific CMOS, [snappiness] did what any of us would do, and hacked two Sony A7ii full-frame mirrorless cameras together to get a combined 24x72mm sensor frame.

Conceptually, the hack is really very simple: a 3D print acts like a T-fitting, with the two cameras held parallel off the arms of the T and the lens making the shaft. Inside, the only optics are a pair of mirrors serving as a beam splitter. Each camera sees half the FOV of the lens in its corresponding mirror, which means the images can be stitched together later to make the double-wide pictures [snappiness] is after.

Of course both cameras must be triggered at the same time, but with what looks like a headphone splitter and an aftermarket remote shutter button, that part works perfectly. The optics, not so much– as always with conceptually simple projects, the devil is in the details, and here it’s the mirror alignment where you’ll find Old Nick. [snappiness] made no provision for adjustments, so everything needed to be designed and built with very stringent tolerances. Somewhere along the way, those tolerances were exceeded; as a result, the two cameras don’t share a focal plane.

That means half the composite image will always be out of focus, or that the main lens needs to be refocused and two snaps taken, rather defeating the point the frankencamera. If [snappiness] attempts a version two, perhaps an adjustment mechanism to focus each sensor would be in order. Still, even if it didn’t work perfectly, he’s proven that the idea is sound, and we can’t imagine many people will see this and argue it isn’t a hack.

The world of film did make all of this easier, perhaps– we’ve seen large-format film cameras out of lego, and a panorama made from four full rolls of 35 mm film. If you know of any other great photography hacks– film or digital– don’t hesitate to send us a tip.

Continue reading “Double The Sensors, Double The Fun, With 2-in-1 Panoramic Camera” →

Game Boy Camera In Wedding Photo Booth

July 27, 2025 by Bryan Cockfield 12 Comments

For those of a certain age the first digital camera many of us experienced was the Game Boy Camera, an add-on for the original Game Boy console. Although it only took pictures with the limited 4-tone monochrome graphics of this system, its capability of being able to take a picture, edit it, create drawings, and then print them out on the Game Boy Printer was revolutionary for the time. Of course the people who grew up with this hardware are about the age to be getting married now (or well beyond), so [Sebastian] capitalized on the nostalgia for it with this wedding photo booth that takes pictures with the Game Boy Camera.

The photo booth features the eponymous Game Boy Camera front-and-center, with a pair of large buttons to allow the wedding guests to start the photography process. The system takes video and then isolates a few still images from it to be printed with the Game Boy Printer. The original Game Boy hardware, as well as a Flask-based web app with a GUI, is all controlled with a Raspberry Pi 4. There’s also a piece of Game Boy hardware called the GB Interceptor that sits between the Game Boy console and the camera cartridge itself which allows the Pi to capture the video feed directly.

The booth doesn’t stop with Game Boy hardware, though. There’s also a modern mirrorless digital camera set up in the booth alongside the Game Boy Camera which allows for higher resolution, full color images to be taken as well. This is also controlled with the same hardware and provides a more modern photo booth experience next to the nostalgic one provided by the Game Boy. There have been many projects which attempt to modernize this hardware, though, like this build which adds color to the original monochrome photos or this one which adds Wi-Fi capability.

Continue reading “Game Boy Camera In Wedding Photo Booth” →

Read QR Codes On The Cheap

July 26, 2025 by Al Williams 15 Comments

Adding a camera to a project used to be a chore, but modern camera modules make it simple. But what if you want to read QR codes? [James Bowman] noticed a $7 module that claims to read QR codes so he decided to try one out.

The module seems well thought out. There’s a camera, of course. A Qwiic connector makes hooking up easy. An LED blinks blue when you have power and green when a QR code shows up.

Reading a QR code was simple in Python using the I2CDriver library. There are two possible problems: first, if the QR code contains a large amount of data, you may exceed the I2C limit of 254 bytes. Second, despite claiming a 110-degree field of view, [James’] testing showed the QR code has to be almost dead center of the camera for the system to work.

What really interested us, though, was the fact that the device is simply a camera with an RP2040 and little else. For $7, we might grab one to use as a platform for other imaging projects. Or maybe we will read some QR codes. We’d better pick up a few. Then again, maybe we can just do it by hand.

A Look Through The Eye Of A Bowling Ball

July 5, 2025 by Fenix Guthrie 16 Comments

If you are anything like us, last time you went bowling, you thought more about how the ball came back to you than actually knocking down the pin. Perhaps you even wondered what it would be like to be a bowling ball making its way back through mysterious and hidden machines. [Wren] and [Erik Beck] did as well, so they set out to make a bowling ball camera to find out.

At the heart of the contraption is an Insta360 X5 camera nestled between water-jet cut metal plates. Because each lens of the camera has a 200 degree field of view, anything in the overlap of the two lenses simply does not appear, so the two metal plates likewise, do not appear. This does leave a somewhat noticeable seam down the middle of the footage, but overall worked out very well. To prevent vibrations in the bowling ball, it can only be rolled along the plate line, making said seam appear in all the footage. Because the stabilization is happening purely digitally, and the camera itself is spinning with the ball, motion blur became an issue immediately. Fortunately increasing the shutter speed fixed the issue, along with an increase in ISO to compensate for the decreased exposure.

Continue reading “A Look Through The Eye Of A Bowling Ball” →