In the late 1990s, motion picture and television production began a process of rapid digitalization with profound implications for cinematographers in Hollywood, as new tools for “digital cinematography” became part of the traditional production process. This transition came in three waves, starting with a post-production technique, the digital intermediate, then the use of high-definition video and digital production cameras, and finally digital exhibition. This dissertation shows how cinematographers responded to the technical and aesthetic challenges presented by digital production tools as they replaced elements of the film-based, photochemical workflow. Using trade publications, mainstream press sources, and in-depth interviews with cinematographers and filmmakers, I chronicle this transition between 1998 and 2005, analyzing how cinematographers responded to and utilized these new digital technologies. I analyze demonstration texts, promotional videos, and feature films, including Pleasantville, O Brother Where Art Thou, Star Wars: Attack of the Clones, The Anniversary Party, Personal Velocity, and Collateral, all of which played a role in establishing a discourse and practice of digital cinematography among cinematographers, producers and directors. The challenges presented by new collaborators such as the colorist and digital imaging technician are also examined. I discuss cinematographers' work with standards-setting groups such as the Society of Motion Picture and Television Engineers, Academy of Motion Picture Arts and Sciences, and the studio consortium Digital Cinema Initiatives, describing it as an effort to protect “film-look” and establish look-management as a prominent feature of their craft practice. In an era when digitalization has made motion pictures more malleable and mobile than ever before, this study shows how cinematographers attempted to preserve their historical, craft-based sense of masterful cinematography and a structure of authority that privileges the cinematographer as “guardian of the image.”