# Exploring Invisible Traces in Historic Recordings

Twentieth-century audio recordings and motion pictures are important primary source materials for both scholarly analysis and public history, but in many cases essential metadata about them have been lost. Kari Kraus will discuss a new collaborative project at the University of Maryland aimed at recovering the date and time on which a recording was made based on analysis of incidentally captured traces of small variations in the electric power supply at the time of capture.

- Kind: Talk
- Year: 2013
- By: Library Of Congress
- Genres: Science
- Archive: [Library of Congress](https://www.loc.gov/item/2021689252/)
- Licence or status: Rights statement at the Library of Congress (as the archive states it)
- Credit: Library of Congress
- Who can watch: Tweens profiles and older (the archive gives no rating; placed by Invisible Network from its collection and subjects)

[Watch now](https://invisiblenetwork.ai/watch/archive/loc/2021689252?play=1)