A viewer, a box of cards, and one idea too many.
In 2021 I picked up a Holmes stereoviewer and a box of Keystone and Underwood stereographs. Looking through it felt like travelling back in time, in real 3D. It was stunning. I went hunting for an old camera so I could shoot stereographs myself, found a Revere 33, and later a Revere 22 viewer, which I cleaned up and fitted with a working bulb.
The collection kept growing. Then I came across the Library of Congress stereograph collection, and an idea took hold: what if I could view those scans on my iPhone, straight through the old Holmes viewer? All I needed was a holder. My Original Prusa Mini had been sitting idle for months, so I started designing, and the iPhone 13 Pro Max holder came out of it. The viewer got heavy after a while, so a tripod mount followed. Now I can sit at the kitchen table and watch hundred-year-old stereographs.
While reading up on stereography I found out that Fujifilm once built a digital 3D camera, so I tracked down a good one on eBay. Suddenly I could shoot 3D myself, but the photos could only be viewed on the camera. The one converter I found ran on Windows, and I work on a Mac. Time to put my development skills to use: a command-line tool that reads both frames from an MPO file, stitches them together and writes out the result. That became version 1.0 of MPOSplitter. I kept adding options, released it, and eventually the same itch turned into MPOViewer for iOS.
