[This entry is a continuation of Keller-Dorian]

Kodacolor was an additive three-color process for amateur filmmakers that used 16mm panchromatic B/W reversal film. The film base was used as support for an optical system made up of semi-cylindrical microlenses engraved onto the base of the film. When shooting, an RGB (red/green/blue) three-banded filter was placed in front of the camera lens: each lenticular microlens on the B/W film reproduced a reduced real image of the RGB filter, which created three different color records behind each microlens.

As early as 1914, George Eastman had been informed of Pathé’s research into the lenticular process and wrote to Léon Gaumont: “[Charles Pathé] is about to bring out a color process which will revolutionize the Industry.” However, Pathé’s research, which had been overseen by Rodolphe Berthon, was interrupted by the commencement of World War I. It was not until 1924 that the Keller Dorian Film Company was incorporated, to pursue research into the lenticular film process and, eventually, to patent methods for embossing film stocks. Although Keller-Dorian was still at the experimental phase, engineers from Rochester were sent to Paris to evaluate the process – Eastman Kodak acquired the 16mm rights to the Berthon-Keller-Dorian patents in 1925. 

In March 1926, during a trip to Paris, en route to a safari in Africa, Kodak founder George Eastman met with the directors of Keller-Dorian and attended a demonstration at company headquarters. A few weeks later, as he approached Port Sudan, in the Red Sea, Eastman wrote a long letter to his vice-president Frank Lovejoy: 

“Last night I had a dream. I dreamed that Mees [the director of the research laboratory] came to Paris to examine the Keller-Dorian process and found no fundamental defects in it and that it was ready to be put into production.” (Eastman, 1926)

George Eastman had foreseen the considerable success that could be achieved by marketing film in “natural color” for the home-movie market and did not seem to doubt that his research team could quickly achieve a scaled-up version of the process, since as early as 1926, he was confident enough to announce the product to the press: “The film in natural colors within the reach of amateur filmmakers.” (Eastman, 1926)

John Capstaff, a research engineer in Rochester, was assigned to develop the Kodacolor process. He was known for his research work on Two-Color Kodachrome and the 16mm format. It took only three years for the Rochester research team under Capstaff to develop the process up to an industrial scale. This research represented a significant financial investment for the Rochester firm.

Kodacolor had a spectacular launch on July 30, 1928, at George Eastman’s mansion in Rochester. Many personalities were invited, including Thomas Edison. At the occasion, 16mm Kodak Model B cine-cameras were lent to the guests so that they could shoot footage of the garden party. That same evening, the films were then screened to the guests in color, arousing their enthusiasm.

The Kodacolor process is the only example of the Keller-Dorian-Berthon lenticular process being exploited at an industrial scale for the amateur film market. (In Germany, Agfa did offer its own 16mm lenticular process called Agfacolor Schmalfilm but it appears not to have been widely taken up). Kodacolor was well suited to amateur filmmakers, who could project the original film, with no need for prints to be made. 

The only drawback of the process was pointed out by George Eastman as early as 1926 in a letter to Frank Lovejoy: “At present there is no method known by which the picture can be copied or duplicated, each picture must be original, this restricts it to the amateur use at present.” (Eastman, 1926)

In the early 1930s, research was carried out at Eastman Kodak's research laboratory to overcome this difficulty in an attempt to adapt the process for film industry use – mainly with Paramount and, after 1945, with 20th Century-Fox. But these attempts failed due to the insurmountable difficulty of obtaining copy prints of sufficient quality for theatrical release.

In 1935, the subtractive Kodachrome reversal process by Leopold Mannes and Leopold Godowsky Jr. was introduced by Eastman Kodak. This technological breakthrough led to the rapid decline of additive color processes such as Kodacolor.