Anyone who wishes to restore or repair old photographs has a new tool available for use. As long as it is a Daguerreotype, experts at the Canadian Light Source, a high-energy X-ray facility in Saskatchewan, have discovered how to restore important details from daguerreotypes that have been written off as beyond recovery.
On the left is the image as it appears to the eye. On the right is the X-ray scan that reveals where mercury was deposited on the metal plate when the daguerreotype was originally produced.
The results are impressive. Madalena Kozachuk, a doctorate student in chemistry at the University of Western Ontario in London, was able to use X-ray beams to map out the distribution of copper, silver, gold and iron on the two plates. She then wanted to see whether she could detect mercury on the plates, but a beam with sufficient energy was not then available at the Saskatchewan facility. To complete her investigation, Ms. Kozachuk travelled to another synchrotron at Cornell University in Ithaca, N.Y. It was there that the glowing atoms of mercury revealed the images on the plates in exquisite detail, astounding the researchers.
You can read more in an article by Ivan Semeniuk in The Globe and Mail web site at: https://tgam.ca/2Ka7TyC.
My thanks to newsletter reader Russ McGillivray for telling me about this story.