This article follows the early history of the Eastman Kodak Company, examining how the photographic company came to be led by experts in chemistry, who created manufacturing processes that were crucial to the mass manufacture of motion pictures. It argues that celluloid film, the substance necessary for motion pictures, was central to the evolution of Kodak into an industrial chemical company. Kodak’s work to manage the specific technological problems and risks created by this material was itself constitutive of the new industrial shape the firm took. In embracing an intraplant goal of purity of raw materials and finished goods, Kodak made it possible for cinema to become a mass medium, with moving images able to look the same way across time and space, over countless copies. Kodak’s transformation, however, was uneven, as the firm’s photosensitive emulsion continued to be made according to far more empirical, secretive, and artisanal procedures, developed by a photographer without a high school degree. These artisanal processes coexisted alongside a highly standardized plant regime, and both were required to make celluloid film. This history demonstrates one way in which broad cultural transformations of the early twentieth century were closely tied to material and practical transformations within industrial firms.