Camera Works
In Chapter Three, North considers "Close Up", the European film magazine published in Switzerland "with the more-or-less constant assistance of H.D." from 1927 to 1933. Noting the "considerable convergence of the literary world and the no longer quite so new medium of the movies" by 1927, North furthers his examination of international modernism's struggle with sound by pursuing the introduction of sound technology into silent cinema as a revealing moment in the history of globalization. Hollywood's attempts to cope with "the foreign problem", or that 9/10 of the world's population in 1927 did not speak English, often by shooting films in five different languages, are contrasted with utopian strategies advanced by the avant-garde that attempted to bring about an international film culture of the future based on global multilingualism or even Esperanto. In Chapter Two, North argued that sound came just as critics were raising silent film to the status of art, and here he shows how these two instances of perceived contamination, sound as intruder into the autonomous visuality of film and sound as divisive force in the international medium of the eye, often inflected or contradicted one another in the pages of the magazine. North concludes by stating: ""Close Up" registers an awareness in modernism of the strangeness opened up within ordinary experience by the new media, which, instead of establishing a new universal language, had exposed the inherent unfamiliarity of languages long in use."
André Charlin
Charlin became involved in cinematography at a time when sound was starting to be added to motion pictures, and began to build equipment for synchronous sound playback.
At first this used 33 rpm records.
The first "talkies" appeared in 1931, and Charlin began working on ways to improve sound quality through better recording technology.
He founded a recording studio in 1933 that produced the sound tracks for many prewar movies, including in 1934 a stereo sound track for Abel Gance's 1927 silent movie "Napoléon".
He moved into techniques for film projection with a 1935 patent for "Cyclope" focussing and a 1938 patent for "Actua Colour" to project colour films which was used in over 1,000 movie theatres by 1948. 
During World War II he turned to making dynamos to power the lamps of bicycles.
In 1949 Charlin stopped producing cinema equipment and sold all his related patents to Philips of the Netherlands.
Early in the 1950s Radio-Cinema, a subsidiary of the Compagnie générale de la télégraphie sans fil, acquired Charlin' company.