Rachel Nordstrom follows up here on her earlier post where she featured several of the daguerreotypes in the Library’s collections.
Daguerreotypes are relatively rare in Scotland, and specifically so within the Library’s collections. The ones we have are lovely examples of the process but not all of them are in pristine condition for various reasons.
The daguerreotype image rests on a silver plate and consequently will easily tarnish if it isn’t sealed or kept in ideal conditions. Typically, the daguerreotype plate is sealed behind a cover glass, however over time the glass can crack or in some cases go missing all together. We had two key examples of this sort of damage in our collections.
One example is the deterioration of an image of a man with some sort of scientific instrument, now identified as a ‘spark generator’. A significant portion of the cover glass had broken away many years ago leaving no image on a good part of the left portion. Although stored in a protective sleeve for the past several years, an area of exposed plate was of concern as any abrasion would have affected the surface of the image.
The other decayed image is of a group of four men; James David Forbes (1809-1868), Principal of the United College of the University of St Andrews from 1859 to 1868; Rev William Brown, possibly the Minister in charge of the first St Andrews (Scots) Church in Buenos Aires from 1829 to 1850; Sir Hugh Lyon Playfair (1787-1861), provost of St Andrews from 1842 to 1861; and Very Rev Prof George Buist (1779-1860), Professor of Church History at St Mary’s College, St Andrews. The photographer of this stereo view was Antoine Claudet (1797-1867), one of the most notable daguerreotypists of the day, who had learned the process from Louis Daguerre himself in France and was one of the first to bring the new photographic process to Britain. The cover glass on this plate had clearly been cracked and been replaced with a simple cover glass to halt the tarnishing which can be seen obscuring the image.
As indicated in the earlier post, the conservation of these two lovely examples has been a long term goal for a while now. However, conserving daguerreotypes is a difficult process as any abrasion to the surface of the plate will completely obscure or remove the image, so it isn’t as simple as a bit of silver polish of course!
In 2016 at a meeting of the ICOM-CC Photographic Materials Working Group at the Rijksmuseum in Amsterdam there was a demonstration of the electro-cleaning of tarnished daguerreotype plates by Dr Bill Wei. The daguerreotype plate is made of silver and copper which means it will act as a cathode when an electric current is applied and this will reduce the silver sulphide, thus clearing off the tarnish on the image. Results are dependent on technique and the speed at which this process is done. This process requires considerable skill to avoid further damaging the daguerreotype, and other chemical treatments are known to be harmful. The two tarnished stereoviews in the St Andrews collections could benefit from this method of restoration and all options were considered.
This year, we decided to reach out to Dr Mike Robinson of Toronto, Canada as one of the foremost experts in the field on the science of the daguerreotype.
Over the past month, Dr Robinson has been working to restore these two stereopairs. And here are the results:
It is very pleasing to see the restoration of a full image which had remained behind the dense tarnishing on the left side of the plate.
The clarity of this image now is quite impressive; although the spot of abrasion in the bottom left corner is unfortunate, there is nothing to be done about the loss of image there. It should also be noted that any remaining hand pigment would have been lost during the electro cleaning. It was agreed that Dr Robinson could replace some pink pigment in the curtains as this was a typical style Claudet was well known for. This is seen in most of his hand-coloured studio portraits with the same setting.
And so, for easier comparison, here the stereo portraits are again, with before and after.
Many thanks to Dr Wei, the Rijksmuseum and ICOM-CC PMWG for demonstrating this process, and to Dr Robinson for his excellent work restoring these two important collection items.
You will be able to see the results in person this October during the St Andrews Photography Festival as the theme for this year is Science & Photography. Check the festival website events line up for further details, specifically on the ‘Science Treasure from Special Collections’ visit on 22 October at Martyrs Kirk.
Photographic Collections Manager