Image Sensors Demystified By [IMSAI Guy]

The February 1975 issue of Popular Electronics had what was — at the time — an amazing project. The Cyclops, a digital camera with a 32 by 32 pixel resolution with 4 bits per pixel. It was hard to imagine then that we would now all carry around high-resolution color cameras that were also phones, network terminals, and so many other things. But how much do you know about how those cameras really work? If you want to know more, check out [IMSAI Guy’s] recent video on how image sensors work.

The video doesn’t cover any practical projects or circuits, but it has a good explanation of what goes on in modern digital cameras. If you don’t know what digital cameras have in common with an octopus, you might want to watch.

If you want to see what the state of the art in 1975 was, have a look at this post. The image sensor in that camera didn’t have much in common with the ones we use today, but you have to admit it is clever. Of course, 1975 was also the year Kodak developed a digital camera and failed to understand what to do with it. Like the Cyclops, it had little in common with our modern smartphone cameras, but you have to start somewhere.

New Part Day: Onion Tau LiDAR Camera

The Onion Tau LiDAR Camera is a small, time-of-flight (ToF) based depth-sensing camera that looks and works a little like a USB webcam, but with  a really big difference: frames from the Tau include 160 x 60 “pixels” of depth information as well as greyscale. This data is easily accessed via a Python API, and example scripts make it easy to get up and running quickly. The goal is to be an affordable and easy to use option for projects that could benefit from depth sensing.

When the Tau was announced on Crowd Supply, I immediately placed a pre-order for about $180. Since then, the folks at Onion were kind enough to send me a pre-production unit, and I’ve been playing around with the device to get an idea of how it acts, and to build an idea of what kind of projects it would be a good fit for. Here is what I’ve learned so far.

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Explore The Cosmos With This DIY Digital Telescope

Getting a closer look at the Moon isn’t particularly difficult; even an absolute beginner can point a cheap telescope towards our nearest celestial neighbor and get some impressive views. But if you’re looking to explore a bit farther, and especially if you want to photograph what you find out there amongst the black, things can get complicated (and expensive) pretty quick.

While building this 3D printed automated telescope designed [Greg Holloway] isn’t necessarily cheap, especially once you factor in what your time is worth, the final product certainly looks to be considerably streamlined compared to most of what’s available in the commercial space. Rather than having to lug around a separate telescope, tripod, motorized tracker, and camera, you just need this relatively compact all-in-one unit.

It’s taken [Greg] six months to develop his miniature observatory, and it shows. The CAD work is phenomenal, as is the documentation in general. Even if you’re not interested in peering into the heavens, perusing the Instructables page for this project is well worth your time. From his tips on designing for 3D printing to information about selecting the appropriate lens and getting it mated to the Raspberry Pi HQ Camera, there’s a little something for everyone.

Of course if you are looking to build your own motorized “GOTO” telescope, then this is must-read stuff. [Greg] has really done his homework, and the project is a fantastic source of information about motor controllers, wiring, hand controllers, and the open source firmware you need to tie it all together. Many of the ideas he’s outlined here could be applicable to other telescope projects, or really, anything that needs to be accurately pointed to the sky. If you’d like to get started with night sky photography and aren’t picky about what kind of things you capture, we’ve seen a number of projects that simply point a camera towards the stars and wait for something to happen.

[Thanks to Eugene for the tip.]

A FLIR One Pro Sees Again, Thanks To Some Nifty Soldering

The Flir One Pro is a thermal camera that attaches to a mobile phone with a USB-C plug. [Gigawatts] has one, and unfortunately managed to drop it, breaking the USB-C plug and rendering the device useless. The plug is separate from the main PCB, an assembly of its own with a flexible cable, but FLIR are not interested in supplying spares. What was the answer? Wire data lines into the device’s charging port, of course!

The One Pro has its own battery, and to avoid draining the phone it is charged through another USB connection, this time a socket. The data lines aren’t connected, which necessitated some very careful soldering of wire-wrap wire to an SMD package to fix. When completed and secured with glue the resulting camera works with a USB-C cable, and there are plans to mount a tripod thread receptacle in the space left by the USB-C plug.

It’s disappointing that Flir choose not to supply replacements for the USB-C plug assembly, seemingly they see the device as a throwaway piece of consumer electronics rather than the expensive instrument that it is. This modification should at lease allow some unfortunate One Pro owners to revive their dead cameras.

If you’re curious about the Flir One series of cameras, perhaps you’d like to read our review.

Volumetric 3D Television Is Here!

Volumetric 3D displays that allow the viewing of full 3D images without special glasses are not unknown in our community, usually taking the form of either a 3D LED matrix or a spinning rotor either with an image projected onto it or holding an LED array. They are impressive projects, but they are often limited in what they can display. Pretty patterns and simple 3D models are all very well, but they are hardly 3D television. Thus we’re quite impressed with [Evlmnkey]’s bachelor’s degree project, which combines motion capture and a volumetric display for a genuine volumetric 3D closed-circuit television system.

Finding the details takes a bit of dredging through the Reddit thread, but the display is an off-the-shelf Adafruit single-sided LED matrix driven by an ESP32, all mounted on a motor with a pair of slip rings for power. Data is fed to the ESP via WiFi, with the PC responsible for grabbing the image sending it as uncompressed frames. There’s little detail on the 3D capture, but since he mentions a Kinect library we suspect that may be the source.

This is perhaps not the highest resolution TV you’ll ever have seen, indeed we’d liken it to the flickering 30 lines of 1930s mechanical TV, but it’s still a functioning volumetric 3D live CCTV system. If you’re interested by 3D displays, you might like to see our examination of the subject.

Thanks [nandkeypull] for the tip.

Legacy Digital Photos, With A Side Of Murphy’s Law

[Dave Madison] came across some old digital photos, and in his quest to access them, he ran into quite a few challenges. The saga brings to mind both Murphy’s Law, and while [Dave] prevailed in the end, it required quite a few more steps than one might expect.

The one smooth part of the process was that Konica’s proprietary software had a handy JPEG export feature.

Here’s the scene: in the late 90s, Konica partnered with photo shops to provide a photo scanning service, delivering digital scans of film photos on 3.5″ floppy disks, and that’s exactly what [Dave] had to work with. The disks were in good condition, and since modern desktop computers still support floppy drives and the FAT filesystem, in theory all one needs to do is stick disks into the reader one at a time in order to access the photos.

Sadly, problems started early. A floppy drive is revoltingly slow compared to any modern storage device, so [Dave]’s first step was to copy all of the files to his machine’s local storage before working on them. This took a bit of wrangling to deal with 8.3 format file names and avoid naming collisions across disks while still preserving some metadata such as original creation date. It was nothing a quick python script couldn’t handle, but that soon led to the next hurdle.

The photos in question were in an obsolete and proprietary Konica .KQP format. [Dave] went through a number of photo viewing programs that claimed to support .KQP, but none of them actually recognized the images.

Fortunately, each disk contained a copy of Konica’s proprietary “PC PictureShow” viewer, but despite having a variety of versions dated between 1997 and 2001 (making them from the Windows 98 and Windows ME eras) [Dave] could not get any version of the program to run in Windows 10, even with compatibility mode for legacy programs enabled. The solution was to set up a Windows XP virtual machine using Oracle’s Virtualbox, and use that to ultimately run PC PictureShow and finally access the photos. After all that work, [Dave] finally had a stroke of luck: Konica’s software had a handy feature to export images in JPEG format, and it worked like a charm.

In the end, [Dave] was able to save 479 out of the 483 images on the old floppy disks, with a reminder that proprietary formats are a pain. The disks and images may have been over twenty years old, but the roots of digital imaging go considerably further back than that. Take a few minutes out your day to read a bit about Russell Kirsch and the first digitized image, that of his three-month old son in 1957.

VESA Arm Turned Low-Cost Overhead Camera Rig

Whether you’re live streaming builds or just want to take your project photography to the next level, you can’t beat an overhead camera setup. Unfortunately, they tend to be cumbersome and more often than not quite pricey. Looking for an affordable solution that could easily be moved out of the way when not in use, [Jay Doscher] had the clever idea of adapting a common VESA monitor arm to give his camera a bird’s eye view of the action.

If you think about it, one of these monitor arms is a nearly perfect base for a camera rig. They’re easily mounted to a desk or work bench, can be quickly repositioned by design, and perhaps best of all, you don’t have to spend a lot of money to get a decent one. A camera is also a far lighter and less awkward payload than the arm was designed to hold, so you don’t have to worry about it potentially dropping your expensive gear. Or cheap webcam, as the case may be.

All [Jay] had to do was come up with a way to securely mount his Sony A7R3 on the end of one. While there’s certainly a few ways you could solve this particular problem, he went the extruded plastic route and 3D printed a beefy adapter plate with the standard VESA bolt pattern. His Smallrig camera cage attaches to the plate, and thanks to a pair of press-fit bubble levels from McMaster Carr, he’s able to get everything lined up properly over the bench.

Of course, there’s an excellent chance you don’t have the same camera as [Jay]. But that doesn’t mean you can’t modify the design of his adapter to fit your own gear. To that end, he’s not only shared the final STLs, but he’s provided a link to the TinkerCAD project that you can actually edit right in the browser.

If you’ve got a light enough camera, you could put something similar together with PVC pipes or even an articulated arm intended for a desk lamp. But if you’ve got a DSLR or other full-sized camera, we think it’s more than worth the $30 USD one of these will cost you on Amazon to make sure your gear doesn’t end up smashing into the deck during a live stream.