Recently I was contacted to update a Find a Grave record for James Parsons in Randolph County. Parsons died in 1857, however I did not have the date of birth listed. I logged onto F.A.G. And noticed a picture had been added to the record by Ron Parsons. The photo looked late 20th century, possibly around 1910-1920, so I sent an email to Ron about the date of the photograph since it didn't match the date of death.
Ron responded quickly and although had some reservations about the photograph he did ask if it could be a daguerreotype. Looking at the photograph closely, I would agree with Ron! So I decided to write a short article on what a daguerreotype is, not that I'm an expert in the field of photography.
A daguerreotype is a photograph which is often regarded as the first viable form of photography. Some examples of daguerreotypes can be seen on display in museums and facilities which maintain materials relating to the history of photography, and replications of daguerreotypes are often printed in textbooks. Taking information for Wiki, the process was developed by Louis Daguerre together with Joseph Nicéphore Niépce. Niepce had produced the first photographic image in the camera obscura using asphaltum on a copper plate sensitised with lavender oil that required very long exposures. The image in a Daguerreotype is formed by the amalgam, or alloy, of mercury and silver. Mercury vapor from a pool of heated mercury is used to develop the plate that consists of a copper plate with a thin coating of silver rolled in contact that has previously been sensitised to light with iodine vapour so as to form silver iodide crystals on the silver surface of the plate. Exposure times were later reduced by using bromine to form silver bromide crystals, and by replacing the Chevalier lenses with much larger, faster lenses designed by Joseph Petzval. The image is formed on the surface of the silver plate that looks like a mirror. It can easily be rubbed off with the fingers and will oxidize in the air, so from the outset daguerreotypes were mounted in sealed cases or frames with a glass cover. When viewing the daguerreotype, a dark surface is reflected into the mirrored silver surface, and the reproduction of detail in sharp photographs is very good, partly because of the perfectly flat surface.-End of source.
Daguerreotypes were only made in a limited number of sizes. While they can be as small as 1 3/8 inch by 1 5/8 inch or as large as 6 1/2 inches by 8 1/2 inches, the majority of daguerreotypes one will find are 2 3/4 inches by 3 3/4 inches in size. The time period for daguerreotypes were 1840 and 1855 and sometimes would appear blury due to subjects having to sit for long periods of time while the exposure process takes place. You can tell a daguerreotype by the way it's cased and the obvious way it exhibits the characteristics of a mirror at many angles.
My “Readers Digest” version of daguerreotype is just that, a small smidgin of information about this fascinating art of photography. You can obviously hop on the net and learn about the process of daguerreotype. The most famous daguerreotype is that of Edgar Allan Poe! Enjoy!