#72: Memories Brought Back to Life with Holograms

I’ve been fascinated by putting imagery from the real world into the Looking Glass. Ever since we started making holographic displays, I’ve loved the idea of a digital shoebox diorama — a tiny scene from another time and place playing out inside this magical display. I’ve always loved the large-scale dioramas in the Museum of Natural History in New York, and the artistry and life in that kind of display.

I’ve always dreamt of a Looking Glass being used in this kind of context, so recently I took the time do an exploration into bringing historical photographs into a 3D Looking Glass Diorama.

To get a scene into a Looking Glass, you either need a 3D model of a scene, or you need pictures of the scene from more than one perspective. Not many people were making 3D models a hundred years ago, but as luck would have it, people have been shooting stereo photos all over the world since their invention in 1838, and there are countless stereographs from history that are publicly available now.

The Library of Congress has an extensive collection of stereographs that are in the public domain and are free to download, so I started exploring their collection. Let me just say, this is an *insane* collection — there are 29,500 stereo photos from all over the world, most over 100 years old. There are photos of joy and war, of dancers and animals, poverty and love, celebration and storms. Someone took a stereo photo of an alligator eating a person. This was a collection of bygone humanity, brought together from countless photographers around the world, covering a huge diversity of cultures and human experience. I was hooked.

I started sifting through the collection and pulling scenes into the Looking Glass. It’s just a delight to see a moment from 100 years ago brought back on my desk — I feel more connected to these people in the past, and they go from being black-and-white relics on a page to a lively miniature scene in front of me. It feels like I’m looking at real people, rather than pictures of real people.

To get a stereo card in to a Looking Glass, I had to first convert the left and right images to a depth map, a way to represent how far every pixel is from the camera. There are lots of useful tools for bringing a stereo photo into a Looking Glass — Stereo Photo Maker and Stereo Tracer both let you just drag in a stereo photo and see it in a Looking Glass a few seconds later. The challenge, though, is working with old stereographs — there are artifacts in individual left and right images, and issues with contrast and exposure wreak havoc on stereo matching algorithms, like you can see in this conversion of an extremely charming ostrich ride in 1900s Paris:

After doing a ton of conversions, I started looking for easier ways to convert old photographs. Stereo photos take some effort to convert — they are very sensitive to rotation, as well as any blemishes in the images, so I was spending a lot of time cleaning up the image before and after the conversion. Around this time, I had been experimenting with a recent google research project called the Mannequin Challenge that uses AI to generate a depth map from a single 2D image. This sped up the conversion work from minutes to a few seconds, and it started feeling less like technical work and more like exploring through the halls of an art or history museum.

The more I look through these old photos, the more I’m drawn to them. One after another, I swipe through moments from the lives of people who lived more than a century ago. These flashes of memory are re-animated, brought back into the world with the help of this magical box on my desk. I love how delightful, relatable and familiar these miniature worlds are, as they drop, one by one, into my shoebox diorama that is overflowing with stories: my own personal, boundless museum.

**this is part of our “100 Days of Holograms” series, where a few of us in the team at Looking Glass Factory post one new wonderful or weird (or both!) use for the Looking Glass holographic display being conjured around the world each day.