2026-02-21 11:00:24
True or false? Your green laser pointer is more powerful than your red one. The answer is almost certainly false. They are, most likely, the same power, but your eye is far more sensitive to green, so it seems stronger. [Brandon Li] was thinking about how to best represent colors on computer screens and fell down the rabbit hole of what colors look like when arranged in a spectrum. Spoiler alert: almost all the images you see of the spectrum are incorrect in some way. The problem isn’t in our understanding of the physics, but more in the understanding of how humans perceive color.
Perception may start with physics, but it also extends to the biology of your eye and the psychology of your brain. What follows is a lot of math that finally winds up with the CIE 1931 color space diagram and the CIE 2012 system.
Some people obsess about fonts, and some about colors. If you are in the latter camp, this is probably old hat for you. However, if you want a glimpse into just how complicated it is to accurately represent colors, this is a fascinating read. You can learn about the Bezold-Brücke shift, the Helmholtz-Kohlrausch effect, and the Abney effect. Maybe that’ll help you win a bar bet one day.
The post winds up in the strangest place: spectroscopy. So if you want to see how color representation applies to analyzing blue sky, neon tubes, and a MacBook display, you’ll want to skip to the end.
We’ve nerded out on color spaces before. In some cases, the right representation is everything.
2026-02-21 05:00:19
Even though digital cameras have lowered the barrier of entry to photography dramatically, as well as made it much easier for professionals and amateurs alike to capture stunning images without the burden of developing film, the technology behind them is considerably more complex than their analog counterparts. In fact, an analog film camera (not counting the lens) can be as simple as a lightproof box and a way to activate a shutter. Knowing that, any kind of film camera could be built for any number of applications, like this 3D-printed panoramic camera from [Denis Aminev].
The custom-built camera works by taking a standard roll of 35mm film, which is standardized to take 36 pictures, and exposing a wider section of the film to create a panorama. This reduces the number of pictures on the roll to 19. This is the fifth version of this camera, called the Infidex 176 V, and has everything a standard film camera would have, from an exposure counter, pressure plate for the film, a winder, interchangable lenses, a viewfinder, and a tripod mounting point. It does take a bit of work to assemble, as shown in the video linked below, but the final result is impressive and delivers a custom finished product not easily found or reproducible in off-the-shelf cameras.
The path to creating this camera was interesting as well, as [Denis]’s first custom film camera was a pinhole camera. From there he moved on to disassembling an SLR camera and attempting to reproduce all of its parts with 3D printed ones. With that in hand, he was able to modify this design into this panoramic camera which he likes because it reproduces the feel of widescreen movies. Although this camera reproduces all of the bells and whistles of a high quality analog camera, not all of these features are strictly necessary for taking pictures on film. Have a look at this minimum viable camera as well.
2026-02-21 03:30:40
Considering that the Nintendo DS already has its own remake of Super Mario 64, one might be tempted to think that porting the original Nintendo 64 version would be a snap. Why you’d want to do this is left as an exercise to the reader, but whether due to nostalgia or out of sheer spite, the question of how easy this would be remains. Correspondingly, [Tobi] figured that he’d give it a shake, with interesting results.
Of note is that someone else already ported SM64 to the DSi, which is a later version of the DS with more processing power, more RAM and other changes. The reason why the 16 MB of RAM of the DSi is required, is because it needs to load the entire game into RAM, rather than do on-demand reads from the cartridge. This is why the N64 made do with just 4 MB of RAM, which is as much RAM as the NDS has. Ergo it can be made to work.
The key here is NitroFS, which allows you to implement a similar kind of segmented loading as the N64 uses. Using this the [Hydr8gon] DSi port could be taken as the basis and crammed into NitroFS, enabling the game to mostly run smoothly on the original DS.
There are still some ongoing issues before the project will be released, mostly related to sound support and general stability. If you have a flash cartridge for the DS this means that soon you too should be able to play the original SM64 on real hardware as though it’s a quaint portable N64.
2026-02-21 01:40:52
For today’s podcast Elliot Williams is joined by Jenny List, and we’re pushing the limits of mobile connectivity as Jenny’s coming to us from a North Sea ferry. We start by looking forward to the upcoming Hackaday Europe, with a new location in Lecco, Italy. We hope you can join us there!
There’s a bumper collection of hacks to talk about, with a novel soft pneumatic display, a CRT-based VR headset, an LCD photographic aperture, and a novel time-of-flight sensor array in the line-up.Then there are 3D printed PCBs, Scotch tape for a lens, and a project to map farts. We kid you not. Finally we wrap up with mind controlled toys, and a a treatise on requirements and specifications in an age of AI.
Or download it yourself in glorious 192 kbps MP3.
2026-02-21 01:31:42
Magnet placement tools are great because they remove finger fumbling while ensuring correct polarity every time. [EmGi] has made a further improvement by making a version that auto-feeds from an internal stack of magnets.
That is a trickier task than one might imagine, because magnets can have a pesky habit of being attracted in inconvenient ways, or flipping around and sticking where they should not. [EmGi] solves this with a clever rack and pinion mechanism to turn a single plunger press into a motion that shears one magnet from a stack and keeps it constrained while the same magnet responsible for holding it to the tip takes care of dragging it down a feed path. It’s easier to see it work in action, so check out the video (embedded below) in which [EmGi] explains exactly what is going on.
This design is actually an evolution of an earlier, non-reloading version. This new one is mechanically more complex, but if it looks useful you can get the design files from Printables or Makerworld and make your own.
The only catch is that this reloading design is limited in what sizes of magnet it can handle, because magnet behavior during feeding is highly dependent on the physical layout and movements. For a different non-reloading placement tool that works with any magnet size and is about as simple as one can get, you can make your own with little more than a bolt and a spring.
Thanks [Keith] for the tip!
2026-02-21 00:30:27
There was a period from the 1970s to the mid-2000s or so when a fixture underneath the family TV set was a VHS videocassette recorder. These were a masterpiece of cramming a color video signal into the restricted bandwidth of an affordable 1970s helical-scan tape deck, which was achieved by clever use of frequency shifting and FM carrier modulation. Very few of us will have had the ultimate iteration of the VHS format though, W-VHS, which managed the same trick but with HD video. But how? [Superchromat] is here with the answer.
W-VHS used a frequency modulated carrier, but instead of splitting luminance and chrominance in the frequency domain like its VHS ancestor, it did so in the time domain in the same way as some 1980s satellite TV standards did. Each line first contained the color information, then the brightness. Thus it sacrificed some color resolution and a little horizontal image resolution, but kept a much higher vertical image resolution. In the video below the break we go into significant detail about the compromises required to pull this off, and if you watch it through you’ll learn something about magnetic tape recording as well as FM.
The W-VHS standard is largely forgotten now as a last hurrah for the format, but it’s still in the sights of the VHS Decode project. The work in this video is helping them retrieve the highest quality images from these tapes, by capturing the raw RF from the heads and using DSP techniques to decode them.
