Researchers investigate some of the first color photographs ever produced

A group of researchers from the EPFL Audiovisual Communications Laboratory were allowed to study some of the very first color photographs ever produced. The photos are typically locked in the vaults of museums around the world and are the original photographic plates and images from scientist and inventor Gabriel Lippmann.

Lippmann won the 1908 Nobel Prize in physics for his method of reproducing colors in photography. Researchers are investigating the photographs and photographic plates, saying that most photographic techniques take just three measurements for red, green, and blue. However, they have discovered that Lippmann's approach captured 26 to 64 spectral samples of information in the visible region.

The inventor used a technique based on the same interference principles that have been used recently to enable gravitational waves to be detected. The technique is also a foundation of holography and modern interferometric imaging. Researchers said that the images and photographic plates represent the earliest multi-spectral light measurements on record. They wanted to see if it was possible to re-create the original light of these historical scenes accurately.

However, the researchers were most interested in seeing if they could create digital copies of the original photographs and better understand how the technique worked. The team discovered some multi-spectral images reflected from a Lippmann plate contain distortions, but the reproduced colors looked accurate to the eye. The team found several inconsistencies when examining the full spectrum reflected from a Lippmann plate and compared it to the original.

Ultimately, the team was able to make their plates using historical processes and verify the modeling was correct. The researchers hope that revisiting the over a century-old Lippmann photographic technique might inspire new technological developments today.