From Shutter to Lens, This 35mm Camera is Entirely 3D Printed

I’ve noticed that a lot of makers harbor a love for older methods of creation, such as traditional photography, alongside newer ones like 3D printing. For some creative individuals, the two technologies complement each other nicely. Film cameras may be getting replaced by digital technology and smartphone cameras, but they haven’t disappeared altogether – thanks in part to people like designer Amos Dudley, who make it a point to preserve older technology through use of the new.

“Analog photography takes the sense of a moment and turns it into a tangible image,” says Dudley in his blog. “My 3D printer turns the content of my thoughts into real shape and form. I wanted to know if there’s a more authentic photograph to be found at the intersection of design and photography – so I set out to make a camera with only a 3D printer.”

To start his project, Dudley made a list of all of the basic elements of a 35mm film camera: the film cartridge, the film path, the film takeup spools, gears to rotate the spools, the shutter, the aperture plane, the lens, the door to the film cartridge, and a lightproof box to serve as the body of the camera. All of it, as it turns out, was 3D printable.

“A 3D printed camera body could look like anything, but I decided to optimize the design for printing speed and material usage,” Dudley explains. “Most of the larger parts are designed without overhangs in one orientation, so they can be printed without supports, straight off the build platform. Separating the body into modules let me prototype each component individually. The shutter and lens are modules, and can be swapped out for different designs without reprinting the entire camera.”

Once he had the design worked up, Dudley began printing the camera’s parts on a Formlabs Form 2 SLA 3D printer. Several different types of resin were needed for the different parts, which varied in strength and flexibility, but Dudley, a former Formlabs intern, had access to plenty of material. To get the camera’s parts to fit together correctly, he printed them with ±0.075mm tolerances and with .25mm clearances so that they would move smoothly.

3D printing the camera’s lens was the hardest part. It couldn’t have been done with a typical FDM printer, according to Dudley. Even using an SLA printer with a clear resin required a lot of post-processing, because the lens printed in a translucent, frosty finish even at the highest resolution of 25 microns per layer. Resin can’t be flame polished like acrylic or acetone polished like ABS, so Dudley’s only option was sanding. A lot of sanding.

Armed with a set of micro-mesh polishing pads and 12,000 grit sandpaper, Dudley spent about five or six hours sanding each lens, but they still weren’t perfect – reflections on the surface were blurry, meaning that the lenses still had microscopic grooves on them. To solve the issue, Dudley built a whole new machine from scratch.

“I decided to try a process similar to what’s used in commercial lens making, where a lens is ground against a spherical form (concave or convex) with an abrasive slurry between the two,” he explains. “I prototyped a machine that would do this for me, hopefully removing an even amount of material from the lens in a way that wasn’t possible by hand.

“The dish is a spherical section with the same radius as the lens. It has an off-axis rotation (spun by a power drill) to make sure the center of the lens gets the same polish as the edges. The lens itself spins against the inside of the dish, joined to a motor by a spring-loaded kinematic linkage that allows the lens to move laterally and ‘float’ against the surface of the dish without losing contact. The lens and dish spinning at different speeds trace a chaotic pattern that approximates randomness. I used lapping compound as the abrasive.”

The completed polishing machine smoothed out the smaller grooves in the lens within a few minutes, though the larger grooves proved to be a challenge that required a coarser grit material. Getting the lenses to capture decent images was a whole new challenge that included a lot of mathematical figuring, simulation with OpticalRayTracer, and yet another handmade machine – a 3D printed lens tester that allowed Dudley to mount the lenses on an existing camera and assess their quality and focal length before installing them on his printed camera.

During his experimentation, Dudley also found that dipping the lens in clear resin and curing it with UV light made it much clearer. The next challenge involved the shutter. After trying and discarding a couple of different designs, Dudley found his answer in a picture of a camera from 1885. Although all he had was a single image of the shutter, it was enough to digitally replicate and optimize the design in Blender.

As it turns out, the shutter design from more than two centuries ago was ideal for Dudley’s 21st century 3D printed camera. Once the whole thing was assembled, he took it out and shot some film, resulting in misty, dreamlike images.

If you’d like to try printing your own camera, all of the files are open source and available on Pinshape. You can also read more details about the process – and see the photographs that resulted from it – here. Discuss further over in the 3D Printed 35mm Camera forum at 3DPB.com.

[Source/Images: Amos Dudley]