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Camera Conversion (Part 3): Motivation, Materials, and Initial Designs

Having gone over the questions of why modify a digital camera in this way, and which camera I’ll modify to start, it seems relevant to give background on upcoming decisions and related motivations.

For several years, the questions of why and how things are made, including where they are produced, have been of much significance to me. I follow Harry Moser’s ReShoring Initiative, and strongly believe in sourcing materials from places where workers have freedom in work and political expression.

For the past year or so, I have been focused on executing 3D CAD designs (in Solidworks and Fusion 360), and outputting them to 3D printing, laser cutting, and CNC. I do this both because I enjoy the process and because I hope we’re at the beginning of a new era of manufacturing, that will bring more creation of real things back to the United States, and I very much want to encourage that change. I’ve done a bunch with projectors, coming from doing a lot with immersive experience collaborations over the past few years, as well as some development for home components and other projects.

Initial Rendering of Titanium Housing Concept (front)
Initial Rendering of Titanium Housing Concept (back)

You may think I’ve already failed in my mission, by starting out with a camera made in China from which to launch the conversion project, but I try to be pragmatic. If I can’t actually build a prototype (that I hope to manufacture under more ideal conditions) without buying from a place without workers rights, I’ll buy it anyway. Generally what I buy is used, so the money has already gone to the manufacturer, and what I pay only has theoretical economical benefit to them.

In my conversion of the camera, aside from the body itself, and the old lenses, I plan to design all components in 3D CAD, for output by workers under fair conditions. I’ve already had some 3D elements SLA-printed for fit and exploration, and included a couple in my last post. I am currently awaiting delivery of a new iteration of the design.

Notes on mount dimensions

I’ve trimmed down the M12 Mount in the Yi, to allow the lens adapter, and hence the lens, to get closer to the sensor. There is a PCB surrounding the M12 Mount; forming a hole 15mm in diameter.

Yi with M12 Mount trimmed

Shortly I’ll have the latest adapter in hand. I want to see how it fits and whether I have latitude to trim the adapter a bit. When I can see this in place, I’ll have to decide between two paths for next steps.

I may optimize my design and then have the adapter that’s now being done in SLA, CNC-ed from titanium or aluminum for this and future cameras. I’ll embed that adapter in the titanium frame I’ve already designed, using three thin sheets of titanium to hold it in place and protect the camera from the weight of the heavier lenses; while remaining extremely light. I love the look of polished titanium, especially when it’s anodized, and that’s what I’ll do in finishing this model.

or

I may design the front plate of the camera as a thicker sheet of brass, into which I will tap a 15.88 mm (0.625 inch), thread pitch 32 TPI, hole to act as the mount for the D-Mount lenses. This approach will require that I somehow pull the sensor forward from the back of the camera to get to a distance from the lens flange to the sensor of 12.29mm. I’d love to tap the mount into a solid front for the camera, as I think this’ll give it a great feel, and secure heft. -the latter also being its downside. While bronze is actually my favorite metal, brass is pretty nice for use with optics, and will be kind to the threads of the lenses.

Rendering of brass-plate component
0.625 inch taps