Posted 3 years ago
There are many posts here on CW showing small daguerreotype images, so I thought to share some information about them.
Daguerreotypes are the earliest practical form of photography that produced permanent images. The process was popular from its 1839 announcement to the early 1850s. Each mirror-like image is unique (no negatives to make reprints) and created on a layer of silver coated on a polished copper plate. Technically excellent daguerreotypes have a delicacy and tonal range unmatched by later photographic processes.
Daguerreotypes are easily distinguished from other forms of pictures because the images look like they appear on a silvery mirror. Later forms of pictures such as ambrotypes (images on glass plates) and tintypes (images on japanned metal) do not have the mirror-like look of daguerreotypes.
This 1/9-plate (2 x 2½ inches) image is a very common portrait style and format often found in simple folding cases meant to be carried as mementos. These portraits were often unsophisticated and straightforward; however, this example shows a decent level of technical execution. Horizontal stripes seen on the plate are scratches more than likely caused from buffing when the plate was being prepared.
A quarter-plate (3¼ x 4¼ inch) or ½-plate (4¼ x 5½ inch) camera more than likely made the picture; they were the most popular size American formats of the time. Reducing masks inserted into plate holders held the smaller, inexpensive plates.
Photographers had to practically be chemists to make daguerreotypes. Louis Jacques Daguerre’s original 1839 five-step process using toxic chemistry was complicated and can be summarized as follows:
1. Polish and immaculately clean a silver-plated copper plate.
2. Sensitize (fume) the plate with iodine vapor.
3. Place sensitized plate in camera and expose.
4. ‘Develop’ the exposed plate by placing over hot mercury vapor until an image appears.
5. Desensitize the iodine to ‘fix’ the image and wash.
Because the jewel-like images are extremely fragile, Daguerre recommended the plates be framed and protected under glass.
The c.1853-54 ¼-plate Palmer & Longking daguerreotype camera with petzval portrait lens, in my collection and posted here on CW, shows the type of camera that could have made the portrait.