Have you ever looked at a blurry, tarnished daguerreotype and wondered about the faces hidden beneath the corrosion? Thanks to researchers at Western University in Ontario, Canada, those lost images are not lost forever – they can be brought back to life.
Daguerreotypes used silver plates to capture an image. Unfortunately, these plates tarnish over time, obscuring the pictures they once held. But this new technique uses X-rays to see through the damage and reveal the hidden image.
Here’s how it works: By focusing a beam of X-rays on the tarnished plate, scientists can track a specific element, mercury (Hg), used in the photographic process. As long as the underlying image particles haven’t been destroyed, this technique can reconstruct the image with surprising quality, even if the surface is badly corroded.
The study also explores using different X-ray energies to achieve the best results. This not only helps retrieve the image but can also provide additional information about the tarnish itself. By analyzing the X-rays in a vacuum chamber, scientists can learn more about the surface and underlying structures of the daguerreotype.
Professor Tson-Kong (T.K.) Sham explains that the team attempted this this experiment in 2018, but they had to refine it. They have now discovered that they can get much better results by using much softer X-rays. They are available at the Canadian Light Source (CLS), a national research facility that offers the only synchrotron light source. It’s a type of particle accelerator capable of producing extremely bright light.
This research is a big win for cultural heritage preservation. It offers a way to recover lost pieces of history and better understand these early photographic techniques. Sham and his team have published the study on the entire process and results, and you can read it here.
[via PetaPixel; image credits: “Retrieving images from tarnished daguerreotypes using X-ray fluorescence imaging with an X-ray micro beam with tunable energy” by Tsun-Kong Sham et al. published in Journal of Cultural Heritage.]
