What camera technology was first used in a feature film by Snow White?

Snow White was the first feature film to use Disney's multiplane camera technology.

The multiplane camera created an illusion of depth by photographing separate layers of artwork positioned at different distances from the lens. Moving those planes independently produced parallax: foreground, characters, and backgrounds could appear to travel at different speeds, making an animated scene feel more three-dimensional.

Disney developed an advanced version of the system during production of Snow White. William Garity designed the camera, which could accommodate as many as seven movable artwork layers. It enabled striking perspective effects, including the swirling environment around the Evil Queen as she drinks her potion.

A common mix-up is saying Snow White was the first film ever to use a multiplane setup. Earlier animation experiments and devices existed, and Disney's camera was tested in the 1937 short “The Old Mill.” Snow White is more precisely credited as the landmark feature-film use of the technology, helping establish animation as a sophisticated cinematic medium.