A Brief History of Movie Special Effects

Everett Collection

The Parent Trap — Doubling
In 1961, Disney scored twice with family classic The Parent Trap. Actress Hayley Mills plays twins Sharon and Susan, who meet by chance at a summer camp after being separated by birth. The trick itself was simple. Using split-screen technology to place Mills into the same scene twice, filmmakers simply locked the camera in position and shot the scene a second time, laying half of each shot onto a single negative to create a composite. The technique has been used in some fashion since the early 20th century. Last year it was David Fincher's The Social Network that had movie fans seeing double. To create identical twins Cameron and Tyler Winklevoss, Fincher filmed actors Armie Hammer and Josh Pence and then layered Hammer's face onto Pence's body.

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