Schüfftan process

The Schüfftan process is a classic film trick that is rarely used today. It was developed by Eugen Schüfftan and Ernst Kunstmann developed by the film Metropolis by Fritz Lang famous.

Figure 1: Setup for the Schüfftan process

The Schüfftan process is one of the combination tricks: Two images are combined here to form one image.

The great advantage of a combination trick is that the proportions of the two images do not matter. The Schüfftan process therefore saves costs when building the scenery : Instead of a large, complex backdrop, a small model can simply be used.

The procedure

For the Schüfftan process, a mirror is set up at an angle of 45 ° to the film camera . Then the backdrop (usually a reduced model) is positioned so that its mirror image takes the desired position in the camera image. The camera does not record the scenery directly, only its reflection.

After the scenery has been correctly positioned, the parts of the mirror layer are removed with a knife, where the actors should later be seen. This makes this part of the mirror transparent.

Figure 2: The result of the Schüfftan process

Figure 2 shows which image the camera takes: Where the mirror is intact, the mirror image of the backdrop appears. Where the mirror layer is missing, the camera can record the actors (through the pane of glass).

Figure 3: Setup for the Schüfftan process (3D)

Figure 4: The result of the Schüfftan process (3D)

Limits

A major disadvantage of the method is that the position of the camera and backdrop must not be changed. For this reason, the method was used almost exclusively for scenes in which the camera does not change its position.