Superimposition, or “multi-exposure” consisted, at the time of photographic film, of putting the same film several times in a row back into the camera. Thus several images were superimposed on the sensitive surface, inseparable forever. It was used to produce fantastic special effects (appearances, multiplications, mixing of scales by Georges Méliès as early as 1895), or poetic effects (in surrealist films in particular, for example “Entr’acte” by René Clair in 1924). It originated before the invention of cinema, in the superimpositions made by means of several magic lanterns, as well as in the projections on a tulle placed in the foreground in the fantasmagorias.
At the age of photographic film, superimposition was definitive and could only be done easily over short periods of time, except in a laboratory, at “truca”, which represented significant costs, with no guarantee of convincing results. The arrival of video mixers in the early 1980s and especially computerized online video editing in the late 1990s freed up the possibilities of superimposition.
Thus, in 2000, with the feature film « Tire », I innovated by superimposing and cross-fading for several minutes, which are not “effects”, but become the heart of a new cinematographic “grammar”. Superimposition, in my approach, is much more than a stylistic effect, it is a way of reinventing the concept of editing, which I experimented radically in Chaosmos in 2014. My reflection on superimposition goes as far as its implementation at the time of projection on various supports in the city, during the travelling projections that I have been organising since 2011.