Darkroom Robot Automates Away The Tedium Of Film Developing

January 8, 2024 by Dan Maloney 14 Comments

Anyone who has ever processed real analog film in a darkroom probably remembers two things: the awkward fumbling in absolute darkness while trying to get the film loaded into the developing reel, and the tedium of getting the timing for each solution just right. This automatic film-developing machine can’t help much with the former, but it more than makes up for that by taking care of the latter.

For those who haven’t experienced the pleasures of the darkroom — and we mean that sincerely; watching images appear before your eyes is straight magic — film processing is divided into two phases: developing the exposed film from the camera, and making prints from the film. [kauzerei]’s machine automates development and centers around a modified developing tank and a set of vessels for the various solutions needed for different film processes. Pumps and solenoid valves control the flow of solutions in and out of the developing tank, while a servo mounted on the tank’s cover gently rotates the reel to keep the film exposed to fresh solutions; proper agitation is the secret sauce of film developing.

The developing machine has a lot of other nice features that really should help with getting consistent results. The developing tank sits on a strain gauge, to ensure the proper amount of each solution is added. To avoid splotches that can come from using plain tap water, rinse water is filtered using a household drinking water pitcher. The entire rig can be submerged in a heated water bath for a consistent temperature during processing. And, with four solution reservoirs, the machine is adaptable to multiple processes. [kauzerei] lists black and white and C41 color negative processes, but we’d imagine it would be easy to support a color slide process like E6 too.

This looks like a great build, and while it’s not the first darkroom bot we’ve seen — we even featured one made from Lego Technics once upon a time — this one has us itching to get back into the darkroom again.

Continue reading “Darkroom Robot Automates Away The Tedium Of Film Developing” →

Use Your Old SLR As A Digital Camera?

October 9, 2023 by Jenny List 42 Comments

Back in the late 1990s as the digital revolution overtook photography there were abortive attempts to develop a digital upgrade for 35mm film cameras. Imagine a film cartridge with attached sensor, the idea went, which you could just drop into your trusty SLR and continue shooting digital. As it happened they never materialised and most film SLRs were consigned to the shelf. So here in 2023 it’s a surprise to find an outfit called I’m Back Film promising something very like a 35mm cartridge with an attached sensor.

The engineering challenges are non-trivial, not least that there’s no standard for distance between reel and exposure window, and there’s next-to-no space at the focal plane in a camera designed for film. They’ve solved it with a 20 megapixel Micro Four Thirds sensor which gives a somewhat cropped image, and what appears to be a ribbon cable that slips between the camera back and the body to a box which screws to the bottom of the camera. It’s not entirely clear how they solve the reel-to-window distance problem, but we’re guessing the sensor can slide from side to side somehow.

It’s an impressive project and those of us who shot film back in the day can’t resist a bit of nostalgia for our old rigs, but we hope it hasn’t arrived too late. Digital SLRs are ubiquitous enough that anyone who wants one can have one, and meanwhile the revival in film use has given many photographers a fresh excuse to use their old camera the way it was originally intended. We’ll soon see whether it catches on though — the crowdsourcing campaign for the project will be starting in a few days.

Oddly this isn’t the first such project we’ve seen, though it is the first with a usable-size sensor.

Wooden Wide-Angle Wonder Wows World

August 23, 2023 by Jenny List 9 Comments

An old-fashioned film camera can be an extremely simple device to make, in that as little as a cardboard box with a pin hole in it will suffice. But that simplicity at heart leaves endless scope for further work, and a home-made camera can be every bit as much a highly-engineered object of beauty as its commercial stablemate. A great example comes from [Aaron Cré], whose desire for something close to a Hasselblad XPan panoramic camera led him to build his own equivalent out of wood.

The video below the break shows in detail how the wooden case is crafted, and how a lens mount ring sawn from a lens adapter is mounted on the front of it. He’s skipped making all the tiresome parts of the camera associated with winding and film transport and instead taken them from a cheap plastic snapshot camera. The original aspect ratio is stretched by cutting the guts of the snapshot camera apart, and extended to make a 75 mm long negative which also exposes over the sprocket holes.

The final camera is carefully finished to the point at which it really looks the part as well as taking those striking wide-angle photographs. We’re not photography buffs enough to identify the lens and shutter combination he’s using, but we can’t help envying him the results. Fancy making your own 35 mm camera too? Here’s another, in case you need inspiration.

Continue reading “Wooden Wide-Angle Wonder Wows World” →

Squeeze Over A Minute Of Movie Filming Onto A 35mm Still Cartridge

May 1, 2023 by Jenny List 14 Comments

There’s an allure to shooting film in the digital age which isn’t quite satisfied by digital filters for your smartphone camera. Aside from the technical challenge of working with a medium limited in sensitivity compared to its electronic replacement there are aesthetic reasons for wanting to shoot with particular lenses not found on any modern cameras. Sadly though, movie film in formats such as Super 8 is expensive to buy and even more expensive to develop.

It’s a problem [Blaž Semprimožnik] addressed with his Okto 35 camera, a unique design that fits a minute and 7 seconds of 8mm-like movie filming onto a much cheaper roll of 35mm still camera film. How does it achieve this feat? By splitting the width of the film into four parallel tracks of 8mm-sized frames.

The camera is a 3D printed design, with all mechanical functions performed by stepper motors to avoid the complex gear trains that would have been found in cameras from the home movie heyday. Each frame advance is a single sprocket hole on the 35mm film, and the track selection is performed automatically by moving the C-mount lens assembly sideways.

The result is a camera which is definitely unconventional, but which delivers something very close to that 8mm experience at a much lower cost per frame. There’s no reflex viewfinder or through-the-lens light metering, but since this is a camera likely to be used by enthusiasts rather than by 1970s consumers we’re guessing this won’t be a problem for most users.

There doesn’t appear to be anything in the way of downloadable STL files or other resources, probably because there’s a possibility he might put the camera into limited production. For the amount of work that he’s evidently put in we wish him luck, and given that the bench on which this is being written has more than one 8mm camera on it, we’re even slightly tempted by one. You might be too, after you’ve watched the video below the break.

This is a novel approach to a 35mm movie camera for still film cartridges, but it’s by no means the first. Previous ones we’ve seen have been full-frame designs though, capturing only a few seconds per roll.

Continue reading “Squeeze Over A Minute Of Movie Filming Onto A 35mm Still Cartridge” →

The Bose headphone plug in question, with reverse-engineered schematic of the filter overlaid.

This 3.5mm Cable Distorts Signals, Hides Audio-Filtering Circuit

April 10, 2022 by Arya Voronova 57 Comments

[Avian]’s dad got a new ham radio transceiver with a 3.5 mm jack, and his pile-of-cables got him a headphone cable from Bose headphones. He built a DB9 to 3.5 mm adapter with that one – and it failed to let data through, outputting distorted garbage of a waveform instead. With a function generator and an oscilloscope, [Avian] plotted the frequency response of the cable, which turned out to be quite far from a straight line. What was up?

Taking the connector apart was a tricky job. A combination of blunt force and a nail polish remover soak didn’t quite get them all the way, so [Avian] continued to apply blunt force and took the jack apart with minimal casualties. Turned out that there was more to the 3.5 mm plug indeed — a whole PCB with a few resistors and capacitors, reverse-engineered into the schematic seen above.

Looks like Bose decided to tweak the audio characteristics of a specific pair of headphones, and an in-plug filter was, somehow, the most efficient solution. We probably shouldn’t expect to see this often, but it bears keeping in mind: next time your repurposed 3.5 mm cable doesn’t behave as expected, it would be prudent to do a capacitance test with your trusty meter or oscilloscope.

With how small MCUs have gotten, you can easily hide more than just a few capacitors! We don’t often see circuits built into cables, but when we do, it’s for malicious purposes.

Accessible Controller Plays Around With Modularity

April 10, 2020 by Kristina Panos 8 Comments

Video games are a great way to have some fun or blow off a little steam when real life becomes laughable. But stock controllers and other inputs are hardly one size fits all. Even if you have no physical issues, they can be too big, too small, or just plain uncomfortable to hold.

[kefcom] wrote in to give us a heads up about a modular, adaptive system he designed for anyone who is unable to operate a PS3, PS4, or PC with a standard controller. The project was inspired by Microsoft’s adaptive XBOX controller and works pretty much the same way — broken-out buttons, joysticks, and other inputs all connect to a hub that unifies them into a controller the console or computer can communicate with. The major difference is that this project is open source and can be realized much more cheaply.

If you want to give this a try, [kefcom]’s project repo has step-by-step instructions for disassembling two types of wireless controllers and converting them into hubs for modular controls. He’s looking for help with design, documentation, and finding reliable suppliers for all the parts, so let him know if you can assist.

Some players need something more accessible than just broken-out buttons and full-size joysticks. Here’s an adaptive controller that uses ridged foam rollers to actuate buttons.

Stomp Switches Let You Skip Tracks Hands-Free

February 24, 2020 by Tom Nardi 11 Comments

You’ve (probably) got four limbs, so why are you only using half of them when you’re working on the computer? Just because your toes don’t have the dexterity to type (again, probably) doesn’t mean your feet should get to just sit there doing nothing all day. In a recent project, [MacCraiger] shows you just how easy it can be to put some functionality under foot by building a pair of media control stomp switches.

Crimp pin connectors grant +50 professionalism.

If the devices pictured above look a lot like guitar effects, that’s because they share a lot of parts. [MacCraiger] used the same sort of switch and aluminum case that you might see on a pedal board, as he figured they’d be better suited to a lifetime of being stepped on than something he 3D printed.

Up on the desk, and this time in a printed case, is the Arduino Leonardo that they connect to. The wiring for this project is very straightforward, with the switches connected directly to the GPIO pins. From there, the Arduino firmware emulates a USB Human Interface Device and fires off the appropriate media control keystrokes to skip to the next track or pause playback depending on which switch has been engaged.

This hardware isn’t exactly breaking any new ground here, but we did like how [MacCraiger] used standard 3.5 mm audio cable and the associated jacks to connect everything up. It’s obviously on-theme for what’s essentially a music project, but more importantly, gives the whole thing a very professional look. Definitely a tip to mentally file away for the future.

For the more accomplished toe-tapper, our very own [Kristina Panos] recently recently took us through the construction of her macro slinging footstool. Between these two examples of bespoke peripherals, you should have everything you need to create your own custom input devices. We suppose you could even make one that’s hand operated if you’re into that sort of thing.

Continue reading “Stomp Switches Let You Skip Tracks Hands-Free” →