A colour photography pioneer comes to light thanks to the synchrotron

The colour prints of Louis Ducos du Hauron, an unknown pioneer of colour photography, have been put under the infrared and X-rays at the ESRF, the European Synchrotron (Grenoble, France) to better understand the methods he used. A team of researchers and curators from the ESRF, CNRS, C2RMF , Musée d’Orsay, École nationale supérieure Louis Lumière, the faculty of Science and Engineering of the Sorbonne University, the Chimie Paris Tech and a private photography conservator and curator has published the results of this study in Angewandte Chemie.

Who invented colour photography?

To this question, most people would reply “the brothers Lumière”. Their procedure “autochrome” is recorded into posterity because the brothers commercialised it with success. However, a photography pioneer has been kept in the shadow: Louis Ducos du Hauron. This is despite the fact that he patented an animated image-processing method in 1864, the same year that Louis Lumière was born. He was the first one to produce three-color prints using three negatives printed into three colour positives (one red, one yellow and one blue), in a similar manner to how printers today function.

As if he were a cook, Ducos du Hauron spent his life creating “recipes” – procedures based on scientific experimentation- to achieve a faithful reconstruction of reality through colour photographs. He photographed each scene through green, orange, and violet filters, then printed his three negatives on three thin films of dichromate gelatin containing red, blue, and yellow pigments, the complementary colours of the filters used for the negatives. When the three positives were superimposed, a full-colour photograph resulted.

>Read more on the European Synchrotron (ESRF) website

Image: General principle of three-color carbon printing developed by Ducos du Hauron. (Full image here)
Credit: ESRF