When photographing the world around us, the property of colour is something most people tend to take for granted. We expect our cameras to portray the visible light spectrum with precision. In a world so obsessed with colour, we sometimes forget that it took a long time to get to this point in time and how many scientists and photographers looked at it as a fantasy!
Few of the first experiments began in the middle of the 19th century. The original approach was to find a material that could directly share the colour properties of the light that fell upon it. The ability to capture colour came in 1851 from a minister called Levi Hill living in upstate New York. He declared that he had discovered a process to make natural colour photographs which he named hillotypes. This was an astonishing claim from someone with no formal training at a time when the world's greatest scientific minds were competing to come up with just such a process. But it was his refusal to share the process that ignited both mystery and controversy for another 50 years as inventors were still dreaming to find a way to make colour photographs. Among those dreamers were the French filmmakers, the Lumiere Brothers - Augusta and Louis. They both were fascinated by photography since their childhood.
The key insight was to create a colour negative by combining three images - one red-orange, one green and one violet. These colours came from fine, microscopic grains of dyed potato starch which the Lumieres called an autochrome. A fine mixture of this powder, a layer thick, was applied to a glass plate. The spaces in between the starch grains were stuffed with lampblack and then the entire plate was subjected to tremendous pressure. A light sensitive silver bromide emulsion was applied after that. Each grain acted as a tiny filter allowing the corresponding coloured light to pass through and expose the emulsion. Once processed, the result was a glass transparency. Until the advent of colour films in 1930s, this was the method of colour processing. This is how the Lumiere Brothers are credited with inventing the first commercially viable colour photograph. The autochrome remained the preferred method for creating colour images and was later replaced by other techniques like Kodachrome and Agfacolour.
Many of these images have been lost over time owing to the inherent fragility of the plate. Few carefully protected archives remain today, leaving behind a rich heritage of autochrome imagery for us to appreciate!