In The Invisible Photograph, Arthur Ou explores evasive photography from our past in a five part series. Whether nearly lost, almost forgotten, or impossibly cryptic, Ou reminds us that these are the projects that can reveal the most about our histories of art, culture, and our pursuit of knowledge.

The project is a part of Carnegie Museum of Art’s  Hillman Photography Initiative and so far has culminated in a piece about Andy Warhol’s Amiga Experiments and the Corbis IMage Vault.

In Part 3, released this July, Ou investigates the Lunar Orbiter Image Recovery Project.