To help Lang realize his vision of having his actors appear to inhabit a breathtaking—and huge—fantasy city, cinematographer Eugene Schufftan applied a process that used mirrors to create the illusion that the actors were inside what were actually miniature sets. A mirror would be placed in front of the actors being filmed, with the backing of the mirror scraped off only enough to make the actors visible. The mirror would be angled so that it would pick up the reflection of the miniature set, placed to the side. The technique came to be known as "the Schufften Process" and was used in numerous films, including Alfred Hitchcock's "39 Steps" (1935), which has also been featured on UEN SciFi Friday.
Of course, Schufftan wasn't the first to rock the video world with F/X magic, nor would he be the last. The Schufftan Process has been likened to the 19th century stage effect called "Pepper's Ghost", in which plate glass combined with careful lighting can make objects seem to appear, disappear or transform, and Schufften's contemporary, Norman Dawn, pioneered the "glass shot" and is credited with refining the "matte shot", techniques on which countless filmmakers have depended. In the 1950s, color film's availability demanded innovations such as the sodium vapor process and the blue screen. And, of course, the integration computer-generated animation into live action has made possible blockbuster delights such as "Jurassic Park" (1993), "Spiderman" (2002) and "Avatar" (2009).