How Much Resolution Does Film Really Have?

September 6, 2024 by Lewin Day 29 Comments

Have you ever scanned old negatives or print photographs? Then you’ve probably wondered about the resolution of your scanner, versus the resolution of what you’re actually scanning. Or maybe, you’ve looked at digital cameras, and wondered how many megapixels make up that 35mm film shot. Well [ShyStudios] has been pondering these very questions, and they’ve shared some answers.

The truth is that film doesn’t really have a specific equivalent resolution to a digital image, as it’s an analog medium that has no pixels. Instead, color is represented by photoreactive chemicals. Still, there are ways to measure its resolution—normally done in lines/mm, in the simplest sense.

[ShyStudios] provides a full explanation of what this means, as well as more complicated ways of interpreting analog film resolution. Translating this into pixel equivalents is messy, but [ShyStudios] does some calculations to put a 35mm FujiColor 200 print around the 54 megapixel level. Fancier films can go much higher.

Of course, there are limitations to film, and you have to use it properly. But still, it gives properly impressive resolution even compared to modern cameras. As it turns out, we’ve been talking about film a lot lately! Video after the break.

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Autochrome For The 2020s

May 12, 2024 by Jenny List 2 Comments

For all intents and purposes, photography here in 2024 is digital. Of course chemical photography still exists, and there are a bunch of us who love it for what it is, but even as we hang up our latest strip of negatives to dry we have to admit that it’s no longer mainstream. Among those enthusiasts who work with conventional black-and-white or dye-coupler colour film are a special breed whose chemistry takes them into more obscure pathways.

Wet-collodion plates for example, or in the case of [Jon Hilty], the Lumière autochrome process. This is a colour photography process from the early years of the twentieth century, employing a layer of red, green, and blue grains above a photosensitive emulsion. Its preparation is notoriously difficult, and he’s lightened the load somewhat with the clever use of CNC machinery to automate some of it.

His web site has the full details of how he prepares and exposes the plates, so perhaps it’s best here to recap how it works. Red, green, and blue dyed potato starch grains are laid uniformly on a glass plate, then dried and pressed to form a random array of tiny RGB filters. The photographic emulsion is laid on top of that, and once it is ready the exposure is made from the glass side do the light passes through the filters.

If the emulsion is then developed using a reversal process as for example a slide would be, the result is a black and white image bearing colour information in that random array, which when viewed has red, green, and blue light from those starch filters passing through it. To the viewer’s eye, this then appears as a colour image.

We can’t help being fascinated by the autochrome process, and while we know we’ll never do it ourselves it’s great to see someone else working with it and producing 21st century plates that look a hundred years old.

While this may be the first time we’ve featured such a deep dive into autochrome, it’s certainly not the first time we’ve looked at alternative photographic chemistries.

Build Your Own RGB Fill Light For Photography

April 19, 2024 by Lewin Day 12 Comments

Photography is all about light, and capturing it for posterity. As any experienced photographer will tell you, getting the right lighting is key to getting a good shot. To help in that regard, you might like to have a fill light. If you follow [tobychui]’s example, you can build your own!

The build relies on addressable WS2812B LEDs as the core of the design. While they’re not necessarily the fanciest LEDs for balanced light output, they are RGB LEDs, so they can put out a ton of different colors for different stylistic effects. The LEDs are under the command of a Wemos D1, which provides a WiFI connection for wireless control of the light.

[tobychui] did a nice job of building a PCB for the project, including heatsinking to keep the array of 49 LEDs nice and cool. The whole assembly is all put together inside a 3D printed housing to keep it neat and tidy. Control is either via onboard buttons or over the WiFi connection.

Files are on GitHub if you’re seeking inspiration or want to duplicate the build for yourself. We’ve seen some other similar builds before, too. Meanwhile, if you’re cooking up your own rad photography hacks, don’t hesitate to let us know!

3D-Printed Automated Development Tank For Classic Photo Films

February 27, 2024 by Lewin Day 7 Comments

[packetandy] had a problem. He was still into classic analog photography, but local options for development were few and far between. After some frustration, he decided to take on the process himself, creating an automatic development tank for that very purpose.

For black and white film, developing is fairly straightforward, if dull and time consuming. The film requires constant agitation during development, which can be dull to do by hand. To get around this, [packetandy] decided to build a development tank rig that could handle agitation duties for him by wiggling the film around in his absence.

The tank itself is created by Patterson, and has a stick on top for agitating the film inside. The rig works by attaching a NEMA stepper motor to this stick to jerk it around appropriately. Rather than go with a microcontroller and custom code, [packetandy] instead just grabbed a programmable off-the-shelf stepper controller that can handle a variety of modes. It’s not sophisticated, but neither is the job at hand, and it does just fine.

It’s a nifty build that should see [packetandy]’s black-and-white photography on the up and up. Meanwhile, if simple development isn’t enough for you, consider diving into the world of darkroom robot automation if you’re so inclined!

A Concrete Solution To Balance And Protect Camera Gear

February 1, 2024 by Danie Conradie 15 Comments

Knocking over expensive camera equipment is an unfortunate occupational hazard when filming projects in a workshop. [Dane Kouttron] wanted to stop sacrificing lights to the cause, so he came up with a practical use for a weeble: A self-stabilizing monopod.

Inspired by a giant scale weeble built by [Colin Furze], [Dane] first did the math to determine the parameters for the build. It’s all about achieving torque equilibrium with a hemisphere of concrete, and [Dane] walks us through the equations, arriving at the conclusion that a 2 lb. camera on 4 foot pole, one needs a hemisphere with a mass of 28 lbs. and a radius of just under 4 inches. To achieve this weight in the given volume would require extra dense concrete with steel shot added.

After some CAD work and 3D printing the 4-part mold was assembled, with RTV silicone sealant acting as both adhesive between the parts and mold release agent. [Dane] first did a test mold with concrete he had laying around. With success achieved, he pursued the real mix but had issues with an error in the concrete-water ratio and the difficulty of mixing in the steel shot. On the second attempt he managed to extract a functional hemisphere from the mold, with the pole held in position during curing by a 3D printed bracket.

The hemisphere bottom of the hemisphere has a flat spot to keep it stable when bumped lightly. [Dane] added a Manfroto quick-release mount to the end of the pole to allow easy attachment of lights and cameras. It might be a bit hefty to carry around, but it’s takes up less floor space than a tripod and is sure to save [Dane] from expensive bumps-turned-crashes.

Camera cranes, small and large, are another great tool for workshop cinematography. For sheer overkill it would be hard to beat an 8-axis workshop-sized motion control robot.

Falsified Photos: Fooling Adobe’s Cryptographically-Signed Metadata

November 30, 2023 by Adam Zeloof 34 Comments

Last week, we wrote about the Leica M11-P, the world’s first camera with Adobe’s Content Authenticity Initiative (CAI) credentials baked into every shot. Essentially, each file is signed with Leica’s encryption key such that any changes to the image, whether edits to the photo itself or the metadata, are tracked. The goal is to not only prove ownership, but that photos are real — not tampered with or AI-generated. At least, that’s the main selling point.

Although the CAI has been around since 2019, it’s adoption is far from widespread. Only a handful of programs support it, although this list includes Photoshop, and its unlikely anybody outside the professional photography space was aware of it until recently. This isn’t too surprising, as it really isn’t relevant to the casual shooter — when I take a shot to upload to Instagram, I’m rarely thinking about whether or not I’ll need cryptographic proof that the photo wasn’t edited — usually adding #nofilter to the description is enough. Where the CAI is supposed to shine, however, is in the world of photojournalism. The idea is that a photographer can capture an image that is signed at the time of creation and maintains a tamper-proof log of any edits made. When the final image is sold to a news publisher or viewed by a reader online, they are able to view that data.

At this point, there are two thoughts you might have (or, at least, there are two thoughts I had upon learning about the CAI)

Do I care that a photo is cryptographically signed?
This sounds easy to break.

Well, after some messing around with the CAI tools, I have some answers for you.

No, you don’t.
Yes, it is.

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Retrotechtacular: Studio Camera Operation, The BBC Way

November 26, 2023 by Dan Maloney 11 Comments

If you ever thought that being a television camera operator was a simple job, this BBC training film on studio camera operations will quickly disabuse you of that notion.

The first thing that strikes you upon watching this 1982 gem is just how physical a job it is to stand behind a studio camera. Part of the physicality came from the sheer size of the gear being used. Not only were cameras of that vintage still largely tube-based and therefore huge — the EMI-2001 shown has four plumbicon image tubes along with tube amplifiers and weighed in at over 100 kg — but the pedestal upon which it sat was a beast as well. All told, a camera rig like that could come in at over 300 kg, and dragging something like that around a studio floor all day under hot lights had to be hard. It was a full-body workout, too; one needed a lot of upper-body strength to move the camera up and down against the hydropneumatic pedestal cylinder, and every day was leg day when you had to overcome all that inertia and get the camera moving to your next mark.

Operating a beast like this was not just about the bull work, though. There was a lot of fine motor control needed too, especially with focus pulling. The video goes into a lot of detail on maintaining a smooth focus while zooming or dollying, and shows just how bad it can look when the operator is inexperienced or not paying attention. Luckily, our hero Allan is killing it, and the results will look familiar to anyone who’s ever seen any BBC from the era, from Dr. Who to I, Claudius. Shows like these all had a distinctive “Beeb-ish” look to them, due in large part to the training their camera operators received with productions like this.

There’s a lot on offer here aside from the mechanical skills of camera operation, of course. Framing and composing shots are emphasized, as are the tricks to making it all look smooth and professional. There are a lot of technical details buried in the video too, particularly about the pedestal and how it works. There are also two follow-up training videos, one that focuses on the camera skills needed to shoot an interview program, and one that adds in the complications that arise when the on-air talent is actually moving. Watch all three and you’ll be well on your way to running a camera for the BBC — at least in 1982.

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