The process description includes the following: "The model is painted with a phosphorus paint and photographed with strong lighting against a black background, then rephotographed with ultraviolet light. This turns the model from a light radiator to a light emitter."
Reverse bluescreen is a visual effects technique pioneered by Jonathan Erland of Apogee Inc.(John Dykstra's company) for shooting the flying sequences in the film Firefox. Erland received a Scientific and Engineering Award from the Academy of Motion Picture Arts and Sciences for this technique.[1]
The patented technique is a variant of the traditional Blue Screentraveling matte process for composite photography. Its objective is to enable the matting of subjects that confound the conventional process, such as those exhibiting reflective surfaces. It derives its name from the fact that it reverses, or inverts, the basic bluescreen process. The basic bluescreen process calls for filming a subject in front of a solid blue backing, frequently a transmission screen rather like a large lightbox with a translucent blue plastic sheet in front of banks of lights, usually fluorescent. A reflective surface on the subject being filmed would result in blue reflections visible to the camera. Since the compositing process entails converting blue in the image into some other background image, such reflections would result in “holes” in the foreground subject with the background scene showing through.
Reverse bluescreen overcame this by coating the foreground subject with a clear fluorescent paint that was invisible under conventional visible light but fluoresced when illuminated by ultraviolet, or “black” light thus inverting the process. Thus the practice was to film a subject, such as the glossy black jet fighter in the Warner motion picture “Firefox,” against a neutral, e.g. black, background and lit with normal stage lights. Then reshoot exactly the same scene (using a precise motion control photography camera system) but with the normal stage lighting replaced by “blacklight” fluorescent lamps. The 360nm U.V. light thus caused the fluorescent paint to glow transforming the plane from black to a glowing object.[2] From this image a male and female traveling matte could be produced that enabled the plane to be composited into any background scene desired.
^Kroon, Richard W. (2010). A/V A to Z an Encyclopedic Dictionary of Media, Entertainment and Other Audiovisual Terms. Jefferson: McFarland & Co., Publishers. p. 564. ISBN0786457406.
