Don Iwerks, the Disney engineer who built the cameras behind Mary Poppins and Circle-Vision, has died at 96

Don Iwerks died on the evening of July 9 at 96. Disney announced the death on July 10, and if the name rings a bell it is probably because of his father. Ub Iwerks drew Mickey Mouse with Walt. Don built the machines.

That is a different job from drawing, and it is not a smaller one. The movies he touched do not work without it.

The Mary Poppins problem

Start with the trick everyone has seen and nobody thinks about. In 1964, Disney needed Julie Andrews to dance with cartoon penguins and stand inside a chalk drawing without a halo of grey fringe around her body. Blue screen at the time gave you exactly that fringe, and it ate the soft edges: hair, lace, anything translucent. Poppins is a movie made almost entirely of hair, lace, and translucent things.

The answer was the sodium vapor process, which lights the subject on a white background under a narrow band of yellow light, then splits the image inside the camera with a prism so one strip of film records the actors and another records a matte of pure black and white. Ub developed it. Don, working the machine shop and the camera department, helped refine it and built the specialized cameras and optical printers that made it usable on a shooting schedule. That is why "Jolly Holiday" still holds up on a large screen in 2026 while digital compositing from fifteen years ago already looks like a video game. The edges are clean because the physics were clean.

The 360-degree camera

The other thing Iwerks is known for is Circle-Vision, the rig of nine to eleven cameras that shot a full circle of the world at once so a room of standing people could be surrounded by it. It opened with Disneyland in 1955 as Circarama, U.S.A., and its first film, A Tour of the West, was thrown onto the walls by eleven 16mm projectors running in sync. He later flew to Turin to teach an Italian crew how to run the camera for Italia '61.

America the Beautiful played in some version at Disneyland for more than seventeen years and then moved through Magic Kingdom, EPCOT, Tokyo Disneyland, and Disneyland Paris. Iwerks always said EPCOT was the peak of the work: two nine-screen Circle-Vision theaters, a five-screen 200-degree wraparound in the France pavilion, and The American Adventure, which was a rear-projection theater with physical set pieces standing in front of the image.

He also engineered the 3D and in-theater effects for Captain EO and built the projection system for Star Tours. Every theme park ride that puts you inside a moving picture is downstream of that plumbing.

After Disney

Iwerks was born July 24, 1929. He started at Walt Disney Productions in 1950 as a lab technician in special photographic processes, got drafted into the Korean War, spent two years in the Signal Photo Corps, and came straight back. In January 1953 he moved to the studio machine shop, made camera technician, and drew 20,000 Leagues Under the Sea as his first feature. He eventually ran the machine shop, the camera service department, and the technical engineering and manufacturing division.

He left in 1986 after 35 years and started Iwerks Entertainment, which built giant-screen theaters and motion simulators and put them in something close to 300 venues in 38 countries. SimEx bought the company in 2001. The Academy gave him the Gordon E. Sawyer Award in 1997, the technical honor that comes with an Oscar statuette. Disney made him a Legend in 2009.

"Don embodied that rare combination of heart, ingenuity, and passion that has always defined Disney," Disney CEO Josh D'Amaro said in the company's statement.

Iwerks himself put it less warmly and more usefully. "There was a 'can-do' attitude I learned from Walt and my father," he once said. "If you're doing a really first-class job, you don't need to worry about the money. It will come."

He is survived by his wife of 54 years, Betty, his sons John and Larry, and his daughter Leslie, the documentary filmmaker. His daughter Tamara died before him.

Father and son share a window on Main Street, U.S.A. at Magic Kingdom. It reads "Iwerks-Iwerks Stereoscopic Cameras." One of them drew the mouse. The other one built the rig that shot it.