HackerTube / Video
This Invention Made Disney MILLIONS, but Then They LOST It!
Corridor Crew

Corridor Crew tracks down Disney's lost sodium vapor prism process, used for Mary Poppins-era transparency mattes. They explain how a narrow sodium wavelength and a beam splitter enabled better compositing than green screen.
Recommended as a fun, informative rediscovery of a lost film-effects technique.
6 Hacker News mentions · 2025–2026