Optical printer

An optical printer is a device consisting of one or more film projectors mechanically linked to a movie camera.

The optical printer is used for making visual effects for motion pictures, or for copying and restoring film material.

It was mainly used to reduce standard prints to 16mm and allowed for operation without a darkroom except for loading the positive film magazine.

Named the Acme-Dunn optical printer, it had several new features compared to its predecessors, but was not made commercially available for the movie industry after the war.

[13] Also, since a new, different piece of film was exposed and printed, matching the exact colors of the original was a problem.

Other problematic artifacts depend on the effect attempted, most often alignment inaccuracies in matte work.

Optical printers have often been used in the recovery of older, damaged film stock which includes the 1989 restoration of Intolerance (1916).

[15] If these scratches and abrasions can be prevented from being captured on the new print, it eliminates one entire area of restoration work.

With the fluid temporarily displacing the air in the scratches and abrasions, refraction simply no longer occurs, so the defects are not reflected on the new copy.

[14][16] This method does not work if the scratches on the emulsion side are deep enough to have removed some of the silver or dye image in the original film.

The third method involves inserting a diffusion filter in the path from the collimated light source to the film.