In 1861, James Clerk Maxwell, a Scottish physicist, showed the first color photographic image to the Royal Institution in London. As an experiment he had Thomas Sutton photograph tartan color ribbons through red, green and blue filters. From the negatives he made three black-and-white transparencies. He projected these onto a screen using three lanterns. Each transparency was projected by the light of the color by which its negative was taken. With careful registration, by which I mean, the alignment of the three projected images with each other, a color reproduction of the ribbons was projected on the screen. This was what would later be called an additive color process.
In 1869, Louis Arthur Ducos du Hauron, a French photographer, described the additive color process and the subtractive color process in his book “Les Couleurs en Photographie”. In both processes three negatives are exposed through three filters. However, in the subtractive color process each negative is used to print a picture in a complementary color. For instance, the negative made by red light is printed to give a cyan (blue-green) picture, the one made by blue light is printed to give a yellow picture, and that made by green light is printed to give a magenta (red-blue) picture. Using a subtractive color process, Ducos du Hauron made a still photograph of the town of Agen, in southwest France, in 1877.
Early color motion picture processes were additive. They required simultaneous projection of several images. The projection equipment needed was thus cumbersome and required careful manual manipulation to achieve exact registration. Today, we remember two kinds of color in early films, neither of which were color photography – handpainted ones like the Lumière brothers’ Serpentine Dance from 1896, and films where entire sequences were tinted – like D.W. Griffith’s Intolerance (1916) or Abel Gance’s Napoleon (1927).
The Technicolor Motion Picture Corporation was founded in Boston in 1914 by Herbert Kalmus, Daniel Frost Comstock, and W. Burton Wescott. After having spent some years experimenting with additive processes, by 1922 Kalmus had abandoned them, and had developed a subtractive process often called two-strip Technicolor.
In two-strip Technicolor, a beam-splitter behind the lens of the camera exposed two frames of a single black and white film, one behind a red filter, and one behind a green filter. The frames exposed behind the red filter were printed on one strip of black and white film, and the frames exposed behind the green filter were printed on another strip of black and white film. The red positive was toned green and the green positive was toned red. The two strips, made of thinner film than regular film, were cemented together base to base to make a projection print. We’re going to show a little bit from the first general release film made by this process. It was The Toll of the Sea, produced by Technicolor in 1922, starring Anna May Wong, which was sort of a pastiche of the story of Madame Butterfly.
A glimpse of this film tells us something about the success, and the failure, of two-strip Technicolor. The success was that no special projection equipment was required. The failure was that the color rendition was not yet true to life. The sea is shown as green, not blue. In addition, the release prints, made of cemented-together film strips, had practical problems. The films would cup, scratch, buckle, and break in projectors due to their uneven thickness, and Technicolor was constantly sending out replacement release prints to theaters.
In 1928 two-strip Technicolor was modified to include a print creation method that used a dye-imbibition process. Two positive matrix films (one red and one green) were created as before, but the image was created on the film by hardened gelatin. The matrixes were soaked in dye baths of their complementary colors. The thicker the gelatin layer, the more dye was absorbed. The matrix films were each placed in contact with a blank emulsified strip of film, transferring the dyes to the blank, which, treated with a mordant to fix the colors, became the source of release prints, ending any projection issues with uneven film thickness. The color on the final film blank was absorbed into its emulsion and not simply printed on its surface. The dye-imbibition process resulted in vivid and vibrant colors, the hallmark of Technicolor. Films using this modified process were made at exactly the right time to use the brand new method of optical sound recording, where synchronized soundtracks were recorded optically on the edge of the film.
By 1932, W. Burton Wescott and Joseph A. Ball had perfected a three-color movie camera. The three-strip Technicolor process was born. Walt Disney had exclusive rights to produce animated films using this process in its first years. It was used in feature film production from 1935 to 1955.
Light entering the camera was split into two beam paths by color, using a filter. One path recorded green light on a single strip of black and white panchromatic film (panchromatic means designed to record the full spectrum of color). The other path recorded blue light on the front, and red light on the back of a piece of bipack black and white film stock, two strips attached base to base. The strip that recorded blue light was orthochromatic film (that is, designed to absorb some light frequencies and not others), and it filtered the light going to the strip that recorded red light, which was panchromatic.
Cameras using this method were quite large, and required sound baffles, or blimps, to permit sound recording without camera noise. The cameras were owned by Technicolor, who rented them to the film studios. Increased lighting on set was also needed because the films used had an extremely slow speed.
Full-color rendition on film through a photographic process was now possible. Today, the fine quality of the color in three-strip Technicolor films is the standard against which subsequent color film methods are measured.