Leica M2Pi

DATE: 2024-12-09

or: This Film Camera Makes Unlimited Digital Photos

This post presents several upgrades to the Leica MPi, a Leica M2 with a Raspberry Pi-powered digital back. The most notable upgrade is a larger sensor capable of capturing daylight photos in color. Other upgrades include an internal battery and support for external accessories like a flash. To enable collaboration and replication, I am open-sourcing instructions for the hardware and software through the project’s repository. To open support for project, I am also releasing a zine of work from the camera, now available to pre-order.

Repository: https://github.com/msgtn/r0b0/blob/mpi/docs/mpi.md

Zine: https://www.kickstarter.com/projects/msgtn/leica-mpi-a-photo-zine

Contact: m {dot} jp {dot} sgtn {at} icloud {dot} com

Update video. Thumbnail image: Washington Square Park (photo courtesy of @isolated_fern).

I have been upgrading and using the camera extensively in New York City: the perfect testing grounds for a camera, and where I started taking street photography “seriously” 8 years ago.1 The camera is now capable of capturing daylight photos in color, compared to the original being monochrome-only in natural light. I installed an internal battery that provides several hours of runtime and easy charging. I also added support for accessories like a flash by exposing the Pi’s GPIOs for further extensibility. This camera is my main camera — among the several digital cameras that I own,2 I use only this camera and my phone.3

Mott Street Eatery

Now in Technicolor

The most notable upgrade is capturing daylight photos in color. As mentioned in the original article, I initially had to remove the IR filter4 from the HQ camera sensor to prevent interference with the camera’s cloth shutter. On the recommendations of others, I purchased a screw-on IR filter from eBay and can now capture accurate daylight colors with minimal processing.

Chinatown

Midtown

Union Square

Enhance. Enhance. Enhance.

The system also now supports a larger sensor. At the tail end of 2023, Arducam released their OwlSight module, a 64MP camera ready-to-use with the Raspberry Pi. Barring independent homebrewed projects, this is currently the largest sensor commercially available for the Pi. With a diagonal size of 11.5mm compared to the HQ camera module’s 7.8mm, the sensor reduces the crop factor from 5.5x to 3.7x; the Voigtlander 12mm, originally a telephoto 66mm, is now a normal 44mm.5

Feast of San Gennaro

NYC Marathon

Manhattan Bridge

Though the sensor works well, there are a few considerations:

  • I faced issues using the sensor on the original Pi Zero, so I upgraded to a Pi Zero 2 with an improved CPU. The Pi can only support 5MP images before attempting a capture freezes the camera.
  • The module comes attached to an autofocus lens assembly. I removed this to get to the bare sensor, but it was a bit precarious and obviously not supported.
  • The sensor seems noisier than the official HQ camera, and there is a “hot spot” gradient in the center of the sensor. I do not know if this is a byproduct of damage or if it’s corrected by the original lens; I apply my own gradient to correct for the extra orangeness.
  • The sensor shows its own housing on the edges, resulting in black areas that look like film sprockets. I actually really like how this looks and have preserved them in the uncropped photos in this post.

Bryant Park

Inwood Farm

Outer Banks

Battery included,

sold separately

I have redesigned the housing to support a PiSugar 3 battery that mounts directly to the Pi Zero 2. The original was admittedly deceptively small: the module was thin, but had to be connected to an external USB battery pack. Not only was this cumbersome, but it also meant that disconnecting the battery would shut off the Pi.

Comparison of the original external battery (left) to the revised housing with internal battery (right). Hot dog baseplate sticker upgrade optional.

The internal battery thickens the module, but it is still overall less mass and volume than the original. The PiSugar supports ~3 hours of uptime6 and I use a USB-C battery pack7 to keep the camera charged for the whole day. The footprint has been reduced, the attachment to the camera back secured, the electronic innards better protected, and the edges chamfered so as to not cut into my face.8

I replaced the shoddy flash sync cables to couple the electronic and mechanical shutters with a dedicated adapter. A bolt in the center contacts the center pin and a cable pinched in the cold shoe socket contacts ground. I also added a row of right-angle headers to expose the outer row of the Pi’s GPIOs for future extensibility, e.g. a new set of buttons or knobs to control shutter speed, ISO, white balance, etc.

Thrice upon a flash

The header row exposing the outer row of the Pi’s GPIOs, connected to the shutter sync cable and the flash trigger (left). The white cable leads to the base pin of a transistor that triggers the flash. The FlashQ Q20 mounts directly onto its transmitter (right).

The original motivation for exposing more GPIOs was to use flash. Syncing the flash to the mechanical shutter through one of the sync sockets would not work: due to the shutter lag between the flash sync socket sending the “button close” signal and the Pi’s software beginning the exposure, the flash will have fired before the electronic shutter began exposing.

Timing diagram of the Leica’s mechanical shutter and the Pi’s electronic shutter. If the flash is synced to the mechanical shutter, it will have fired before the electronic shutter began exposing. The “opening” of the electronic shutter begins a thread that fires the flash several times until the exposure is complete.

To sync the flash to the electronic shutter, I connect the flash trigger to a GPIO on the Pi. Simple two-contact flashes like the FlashQ Q209 are triggered by simply closing the circuit between the center pin and ground. Just like how the closing of the mechanical shutter provides an input signal for the Pi to begin an exposure, the Pi can electrically close the flash circuit with an output signal to a transistor. I spliced a transistor into a sync cable to control the flash from the Pi’s GPIO.

Electronic diagram of the system. The shutter button (left) is an input switch that begins an exposure. Beginning an exposure outputs voltage to the transistor base, triggering the flash (center; the flash is represented by the red LED). The directional pad for selecting shutter speed is represented by the buttons (right); counter-clockwise from the top: 1/2, 1/15, 1/60, 1/250.

In software, beginning an exposure also starts a separate thread to output voltage from the GPIO to the transistor’s base. The transistor closes the circuit and triggers the flash. Because the shutter lag is variable, I widen the window of catching the flash in the exposure by setting the shutter speed to 1/2s. The flash thread will repeatedly switch the transistor at a 1/6s interval until the exposure is complete and the file is saved. The flash can fire up to three times, but occasionally still does not get caught in the exposure.10 But when it works, the results are nice.

NYC Halloween Parade

NYC Halloween Parade

NYC Halloween Parade

What I work with when I work on my photography

Me: “I’m still working on this —”

Bruce Gilden: “No, you’re working with that; you’re working on your photography.”

Scene on the corner of Canal and Mulberry (left) and me using the MPi (right, photo courtesy of Mikey).

I actually use this camera,11 and there is nary a better testing ground than New York City. As expected, the camera handles somewhere between a digital and film camera: I cannot spray like digital but I am not as conservative as with film. Because everything is manual, I am much more confident with rangefinder focusing and reading light with the meter in my head.12 Cranking the film advance to arm the shutter is a feeling matched only by the venerable Epson R-D1.13

Manhattan Bridge

Radio City Music Hall

Protest outside Trump’s Madison Square Garden rally

Central Park

New School Library

Yes-talgia machines

I’m appreciative of the enthusiasm for the project, especially as I meet other photographers out and about. Among the responses, some rightfully questioned why, if I want to use a film camera, I wouldn’t just use film. Others linked to counter arguments14 and threads against experiments in digital-film conversions.

Admittedly, the critics have a point. This system does not render with the razor sharpness of a modern digital camera, and it has a litany of quirks: lower battery life, shutter lag, occasional software glitches, etc. As stated in the prior post, a primary motivation is to address the respective unsustainabilities of digital and analog photography with a homebrewed hybrid system. Another motivation that I only glimpsed at is the importance of technological agency, which can address issues in the commodification of our relationship with technology.

BackMarket advertisements for an older iPhone (left, sourced from Carl Quintanilla) and a refurbished Sony camcorder (right).

I’ve recently seen several subway ads for BackMarket, an online reseller of used devices with the commanding slogan: “downgrade now.” An ad for older iPhones reads: “shrink different;” a pun on Apple’s “think different” tagline, not only does the ad convey the individualism of the original, but it also effects a nostalgia through its use of reference. A more obvious appeal to nostalgia is another ad for a Sony camcorder with the tagline “yes-talgia,” for “re-introducing” a refurbished product.

The commercialization of nostalgia is neither novel nor unique, and sells anything from soda to jeans to cameras. We can note the recent pastiches of digital cameras designed to look like film cameras and invite being mistaken as such. Film’s revival is ever-growing despite inflating costs, with Kodak planning to upscale its film production capacity. As the BackMarket ad shows, even 00’s-era point-and-shoots are experiencing a comeback despite being technically inferior to modern phones. The pronounced nostalgia of photographic equipment echoes photography’s inherent nostalgia as a recorded medium.

“One time, a guy handed me a picture and said, ‘here’s a picture of me when I was younger.’ Every picture is of you when you were younger.’” — Mitch Hedberg

The once-invisible and -undesirable aesthetics of a medium become fetishized and their replication becomes deliberate technique: in film, grain, the use of monochrome, sprocket holes; in digital, timestamps, low-fidelity, high noise. Simulating these traits signifies individual taste, whether the nostalgia was actually experienced or just borrowed. I avoid moral judgement of nostalgia and individualism, but affective appropriation to coax behavior always warrants critical attention, especially when the intent is commercial.

An illuminating lens is Marshall McLuhan’s metaphor of the rear-view mirror: we “look at the present through a rear-view mirror,” preoccupying ourselves with looking at the past as we “march backwards into the future.” Nostalgia distracts us from understanding the present technological milieu as it happens and fosters a passive acceptance of the current state of technology.15 In the context of photography, the aforementioned marketing suggests that relief and individual taste can be found in the re-purchase of nostalgic devices. Commercially packaged nostalgia comes bundled with a type of individualism: one can “think different” with the “yes-talgic” quirks of expired film and low-resolution electronics.

Rather than bemoan change, McLuhan calls for an agency with the technology — “turn ivory tower into control tower” — to understand and engage with its affective effects on our own terms. Maintenance of equipment not only preserves utility, but also fosters a connection that promotes the object from disposable tool to future heirloom. Extending equipment through customization or creating altogether new designs affords an individualism that purchase could never provide. Just as the history of photography was written with experimentation in interfaces, chemistry, and optics, technological agency empowers us to actively write the future of the medium rather than passively accept only the marketable.

With the ever-growing accessibility and capability of hardware and software tools, the time is ripe for experimentation. I do not refer to the reskinning and marking up existing products or mass appropriation of artists’ work, but rather projects like adapting increasingly larger sensors for hobbyist use, homebrewed interfaces, or preserving endangered techniques with modern technology. Experimentation inevitably yields imperfection, but the aesthetic of failure is its own reward.

“’One day, we will regret so much accuracy and artists will try to create chance accidents deliberately. Kodachrome film changes colours of its own accord, in the most unexpected way. To a certain extent, it creates. We have to accept this as if it were a painter’s interpretation and accept the surprises. It doesn’t show what I want, but what the camera and the chemical baths want. It’s another world where it’s essential to forget the one we live in.’ — Jean Cocteau” — a commenter on PetaPixel’s MPi article

Repo, man

It’s my hope that we can retrieve the creativity and inventiveness that shaped the instruments of our expression and communication. In support of experimentation, I am releasing the files and instructions for replication and collaboration through the project’s repository.16 The software is built on r0b0, a hardware-software interface library originally developed for the Blossom robot, but generalizable to mechatronics projects such as this or robotizing an IKEA death star lamp.

Spatial Parkinson’s law: work expands so as to fill the time space available for its completion.

The instructions are very much in a beta state, and I plan to improve them in the coming weeks. I am including the CAD files; though these are designed for the M2, the only component that should need major redesigning is the large back plate that mounts the module to the camera in place of the film door.

I am also considering donations of cameras that others would like me to adapt, or commissions for custom integrations directly from me.

print(zine)

The back (left) and front (right) cover of the zine.

To support the project, I am releasing a zine with work I have made with the camera.17 After a few years-long period of little photography, this project has been a revelation in relearning how to see. Not only do development and producing work take time, but unlike a software-only project, component costs add up. Dismayed as we are by the state of online content being appropriated en masse, I have reserved some of my favorite work exclusively for this physical monograph.

The zine will be A5 size (148mm x 210mm) and will contain at least pages of photographs. Pre-orders are available here with a projected release in February; in the case that I miss that date, I will extend the zine with work from an upcoming trip to Asia for a release in early March.

Conclusion

Maker Faire Coney Island (Stereographic GIF courtesy of Cyril Engmann and his PIMSLO camera).

I presented several upgrades to the original MPi, including the capability to capture daylight photos in color, an internal battery, and support for external accessories like a flash. I am releasing the design files and am inviting anyone interested in helping development by donating cameras or commissioning custom modules directly from me. I have used the camera extensively in real-world settings and am releasing a zine of this work, now available for pre-order. This ongoing work is in service of reclaiming technological agency with our instruments.

Repository: https://github.com/msgtn/r0b0/blob/mpi/docs/mpi.md

Zine: https://www.kickstarter.com/projects/msgtn/leica-mpi-a-photo-zine

Contact: m {dot} jp {dot} sgtn {at} icloud {dot} com



  1. Just like 8 years ago: starting a new phase of life; moving to (somewhere in) New York (state); flaneuring with a “new” rangefinder(-like) camera (X100T, now the MPi); Trump is elected. ↩

  2. Digital cameras in order of increasing use: Fujifilm X100V, X-T3, and XF10. ↩

  3. I recently switched from a decade on iPhone to the Samsung Galaxy Fold 4. I am never going back. The affordance of writing on a notebook-like device that fits in a pocket totally transforms what one can do with a phone. I drafted, wrote, and edited most of this post on the phone, in a mix of handwritten notes and typing with a small bluetooth keyboard with a pointing nub (Motorola KZ450). ↩

  4. I erroneously referred to the IR filter as the anti-aliasing filter — thanks to those who corrected me and suggested using a screw-on IR filter. ↩

  5. Could have calculated the effective focal length from knowing the sensor diagonal: 40-45mm is considered “normal” on 35mm (36mm x 24mm) with a diagonal 43.2mm, so a 12mm on an 11.5mm diagonal is very close to normal. ↩

  6. I should be getting more battery life — I suspect the draw might be the LCD module, as its backlight is off but it still gets warm. ↩

  7. The Anker 521 PowerCore Fusion doubles as both a battery pack and a wall charger — great product. ↩

  8. I actually do have a scar on my face in the same location as Luffy. ↩

  9. I probably should have just used the modeling light, which would have avoided all these sync issues. ↩

  10. This may be a useful standalone device for retriggering flash with a slow shutter speed for a double exposure-like effect. ↩

  11. There’s a joke here about how even “actual” Leicas aren’t actually used as cameras, but as jewelry. ↩

  12. Though I could set the software to aperture-priority by calculating shutter speed and ISO, I like improving my light-reading by setting exposure manually. The directional pad sets shutter speed (up for 1/2, left for 1/15, down for 1/60, right for 1/250) and the ISO is hardcoded to 400 (the usable range seems to be 100-800). In practice, I use only a few combinations based on sunny 16: Is it sunny? f16 1/250; Is it cloudy? f11 1/250; Am I in the shade? f5.6 1/250; Am I inside and it’s moderately bright? f5.6 1/60; Am I inside and it’s dim or am I in the subway? f5.6 1/15. ↩

  13. I briefly owned an R-D1 that was featured on Tokyo Camera Style. It is still the only camera I regret selling. ↩

  14. Unsurprisingly written by someone who owns a camera store. ↩

  15. Marshall McLuhan Interview from Playboy, 1969: “I call this peculiar form of self-hypnosis Narcissus narcosis, a syndrome whereby man remains as unaware of the psychic and social effects of his new technology as a fish of the water it swims in.” ↩

  16. Note that the license is permissive but you must distribute derivative works with the same open-source license. ↩

  17. To my knowledge, this may be the first published work from such a homemade hybrid digital-film system. ↩