Wet-transfer film gate

A 35 mm optical printer with two projector heads, used in producing movie special effects and film restoration. Starting from the left, light is shining from the lamp house, then at A is the first projector's film gate, at B a lens that projects the film in A onto the second projector's wet gate C (note the white hoses for the liquid). At D is the lens of the camera, the camera's finder is at E and the adjustable shutter control at F. The heavy base G contains all the electronics needed for controlling the printer.

A wet-transfer film gate, or wet gate for short, is a film gate that is submerged in liquid, used for film restoration and archival scanning. Submerging the film in the gate in a liquid with a suitably matched refractive index reduces the effects of scratches on the film, by reducing the refractive effects which divert light that passes through the scratched part of the film. The liquid also acts to lift other forms of defects from the film.^[1] Perchloroethylene, a hazardous substance with multiple health and safety risks, is commonly used as the liquid medium in wet gate systems,^[2] requiring substantial precautions to be taken to ensure the safety of operators and to prevent pollution.^[3]

Wet gate transfer is often preceded by other forms of film cleaning, such as the use of ultrasonic film cleaners.

References

^ "ARRI Presents Wet Gate for 16mm Scanning". ARRI. Archived from the original on June 7, 2014. Retrieved 2014-06-02.
^ Douglas Bankston. "Wetgate Scanning by Imagica". American Society of Cinematographers. Retrieved 2014-06-02.
^ "Use of Perchloroethylene in Motion Picture Wet-Gate Printing" (PDF). Rochester: Kodak. March 2003. Archived (PDF) from the original on 13 December 2020. Retrieved 13 December 2020. Perchloroethylene, or simply 'perc', is regulated extensively by existing health, safety, and environmental laws. While using perc as a chemical processing aid, workers must be protected against the vapors caused by fugitive losses from the process. Likewise, existing regional and local (e.g., southern California) air pollution regulations may impose further restrictions on usage and emission controls. At the end of its useful life, waste perc is subjected to a strict waste management regime that may include many regulatory restrictions associated with recycling activities. Furthermore, national and local 'right-to-know' laws may require facilities that use perc to disclose information to the public regarding the usage and subsequent management of the chemical.

References

See also