A chemigram is an artistic creative technique, the outcome of an experimental action that combines a number of chemical substances used in photography on a sheet of photosensitive paper. It is a practice akin to photography, but one that does not use a camera, film or negatives. This particular technique was invented by Belgian photographer Pierre Cordier in the 1950s, though similar experiments had been carried out earlier in other countries. In the 1920s, experimental photographers such as Laszlo Moholy-Nagy and Man Ray created new techniques, such as Photogrammetry and Solarisation; later, the Postwar European context would witness the appearance of Subjective Photography (Otto Steinert) and Generative Photography (Gottfried Jäger).
Henrique Vieira Ribeiro uses this process, which descends from photography but does not draw its self-referential images from reality, to develop this series of ten chemigrams alongside the Sal da Terra series.
Though separate, the two series complement one another, since Provas de Contacto [Contact Proofs] acts as a counterpoint to the extremely naturalistic quality of the previous series. In this case, we observe an intervention: instead of developing an image taken from reality by means of a photographic camera, Henrique Vieira Ribeiro creates the image himself without resorting to the camera, using a gestural action close to painting, a manual application of such products as salt, developers, fixers, etc. on photographic paper. This subversion of the photographic process generates, through the actions of chance, a number of morphological effects whose visual outcome amounts to what we may call abstract mini-landscapes.
Unlike conventional photographs, which can be duplicated from a negative, chemigrams are always unique pieces.