The daguerreotype was one of the earliest forms of photography. It is a permanently fixed, mirror-like silver image on a polished copper plate. By adjusting the angle it is held by, you can see a positive or a negative image, or it can appear like a mirror. It was a one-off and very delicate – the image can be destroyed by touch.
The daguerreotype was encased in an enclosure made from a variety of materials – glass, wood, leather, textile and paper. These materials all deteriorate differently and may also interact deleteriously with each other. This means that there is no perfect way to treat and store the whole object.
This 1850s daguerreotype of Melbourne had been dismantled previously. It was in pieces and very dirty. The image was very faded and difficult to decipher either with the naked eye or normal photography.
Conservator Rebecca Main removed the glass, matte and daguerreotype plate from the case and cleaned them. Because the daguerreotype itself could not be touched, the loose specks, dust and pieces of grit were removed by blowing on it with a photography dust blower.
The cleaning made the image a bit more readable, but it was still very faint to the eye. While cleaning it had become apparent that the negative image was sharper, with much more visible detail than when viewed as a positive.
The uncovered, cleaned image was then re-photographed by photographer, Chris Brothers. The previous photos had been of the plate as a positive image, this time it was done as a negative image. The plate was held at different angles by Rebecca until the image was at its clearest. Chris took photos of the plate in sections, with a flat softbox light almost directly behind the photographer, making it possible to capture the negative image. Taking photos of the daguerreotype in sections allowed for much flatter and consistent lighting as well as improving the quality and details.
Using the Photoshop computer program, the different images were composited –stitched together and inverted to create a new positive image. This revealed far more of the original detail of the daguerreotype.
The combination of conservation treatment, digital photography and image manipulation made it possible to retrieve visual information which had appeared lost when the object was examined by a conservator in 1983.
The reassembled object is stored in a clamshell box. The box is constructed from acid free mountboard containing Zeolites or molecular traps. If there are chemicals given off from the daguerreotype or it’s enclosure materials, they will be absorbed by the zeolites. This will create a more neutral micro environment that will help stabilise the object.
Because the photoshopped image contains far more easily visible information, the actual object can safely remain in storage, and the digital image can be used as a research resource.