The inexpensive Kodak Brownie[1] was the first camera to bring photography to the masses. The simplicity of its design meant anyone could figure out how to use it with little difficulty. Because it has essentially no controls to learn—there's just a shutter button, viewfinder, and film winder—it's even easy to use in comparison to today's cameras.
Millions of Kodak Brownies were made over the course of its 60-year lifespan beginning in 1900, and its build quality means many of them survive in good working order. A Kodak Brownie is also a good option for custom modifications—it's easily available on eBay or at tag sales, it's simple to hack, and it's cheap enough that it doesn't matter if things go wrong.
My original plan was to build a variant on the pinhole digital camera[2] I'd previously made with a Raspberry Pi and a webcam. I had an extra Raspberry Pi Zero that needed a purpose and a Kodak Brownie Hawkeye[3], the variant from the 1950s with a case made out of Bakelite instead of wood or cardboard, which I'd bought for less than £5 at a local tag sale. The only key missing piece was a webcam.
Because I'd paid less than £5 for the Raspberry Pi Zero and Kodak Brownie, I set that as my upper price limit for a webcam. Trawling eBay listings, I found a number of sellers offering a variety of 50-megapixel cameras[4] at this price point. These technical specs were untrue—there would never be a 50MP sensor selling for that price—but it was worth a punt to discover just what the camera offered. The one I bought only provided 640×480, a mere 0.3MP with raw video only, no MJPEG[5], thus