Cross pollination

Every year for the past eight years I have attended NI Week - the annual get together of the customers, distributors and staff of National Instruments. Before setting off to Austin, Texas, however, I decided to make a slight detour to Los Angeles, CA to visit my wayward son who had decided to quit his rather lucrative sound engineering position in Boston to pursue a career in film.

On the second day of my visit, I decided it might be interesting to tour Paramount, the last major film studio located in Hollywood. Upon our arrival my son and I were whisked around the back lot on a golf cart that our tour guide stopped at various locations including the "Technicolor at Paramount" facility, an audio post production facility located in the center of the lot.

Always wishing to engage her captive audience, our tour guide asked if anyone knew the first film to have been shot in Technicolor. Silence ensued. Then to my horror she revealed that it was "The Wizard of Oz," a minor tale released in 1939 about a young lady called Dorothy who has a bad dream.

Film cognoscenti will realize, of course, that this motion picture was not the first to be filmed in Technicolor. It was "The Gulf Between" (1917), a tale of a young girl raised by a sea captain and starring the late Grace Darmond.

Of course, the Technicolor process used back then was far removed from the one we know today. To attain the perception of color, a prism with a red and green filter was used to split the light into two color components. This was then exposed simultaneously onto two consecutive frames of black and white film running at double-speed.

Needless to say this process was expensive and required both modification of conventional camera system and the projector used to display the film. After years of further research, such seemingly antiquated methods were replaced with color film negatives that image three primary colors in three separate layers on one strip of film.

Today, many cinematographers are complimenting and even replacing color film in their productions with digital cameras. Interestingly, the highest resolution cameras used today employ prism blocks and three separate image sensors to capture RGB images. In this way, they exhibit increased resolution and eliminate any image interpolation artifacts that may occur when single imager Bayer color filter implementations are used. This is true of both cameras used for high-end cinematography and machine vision applications.

Interestingly, only one company – Foveon – has attempted to model the concept of a three layer color film in a semiconductor device. However, even after sixteen years the technology has yet to find favor among either machine vision developers or cinematographers.

Despite this, it is interesting to see how the digital technologies used today have mirrored the developments of the film accomplishments and techniques of the past.