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Double exposure

The other basic technique for trick cinematography involves double exposure of the film in the camera, which was first done by George Albert Smith in July 1898 in the UK. Smith's The Corsican Brothers (1898) was described in the catalogue of the Warwick Trading Company, which took up the distribution of Smith's films in 1900, thus:

"One of the twin brothers returns home from shooting in the Corsican mountains, and is visited by the ghost of the other twin. By extremely careful photography the ghost appears *quite transparent*. After indicating that he has been killed by a sword-thrust, and appealing for vengeance, he disappears. A 'vision' then appears showing the fatal duel in the snow. To the Corsican's amazement, the duel and death of his brother are vividly depicted in the vision, and overcome by his feelings, he falls to the floor just as his mother enters the room."

The ghost effect was done by draping the set in black velvet after the main action had been shot, and then re-exposing the negative with the actor playing the ghost going through the actions at the appropriate part. Likewise, the vision, which appeared within a circular vignette or matte, was similarly superimposed over a black area in the backdrop to the scene, rather than over a part of the set with detail in it, so that nothing appeared through the image, which seemed quite solid. Smith used this technique again in Santa Claus (1898).

Georges Méliès first used superimposition on a dark background in La Caverne maudite (The Cave of the Demons) made a couple of months later in 1898, and elaborated it with many superimpositions in the one shot in Un Homme de têtes (The Four Troublesome Heads). He created further variations in subsequent films.