There’s been a renewed interest in uncovering the secrets of the earliest colour photography techniques. Among the first few to propose a way to reproduce colours in photography was Gabriel Lippmann, who awarded the 1908 Nobel Prize in Physics for his method. His approach, known as interferential photography, was rather complicated but produced very beautiful colour photographs and was until now believed to be perfect.
Researchers at the Swiss Federal Institute of Technology Lausanne (EPFL) have, however, uncovered new facts about the technique. While most photographic techniques take into account just three colour renditions (red, green and blue), the Lippmann method could typically capture 26 to 64 spectral samples, they wrote in the Proceedings of the National Academy of Sciences.
Gilles Baechler, one of the paper’s authors, and his team of researchers have found that the multi-spectral images reflected from a Lippmann plate contained distortions, but the reproduced colours looked perfect to the eye.
When the researchers compared the full spectrum of colours reflected from a Lippmann plate to the original, they found a number of inconsistencies, many of which they said have never been documented.
“We were able to capture the light reflected back from it and measure how it differed from the original," explained Baechler.
The researchers, who were offered access to some of the original photographic plates and images of the scientist, believe revisiting the over-a-century-old Lippmann’s technique can inspire new technological developments now. They have devised an algorithm to reconstruct the original colours of Lippmann-plate images.
The team has already prototyped a digital Lippmann camera.
Lippmann was born in the European country Luxembourg on August 16, 1845. The Lippmann process utilizes the natural colours of light wavelengths instead of dyes and pigments. This direct method was tedious and slow because of necessarily long exposure times but it did help in the development of colour photography. His work is recorded at the Paris Academy of Sciences.