A daguerreotype is a photograph produced using the daguerreotyping process. Daguerreotypes are often regarded as the first viable form of photography, although the technique was quickly supplanted with more effective photographic processes. 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 so that readers can see what historical figures and places really looked like.
The process was developed through a joint effort between Louis Jacques Mande Daguerre and Nicephore Niepce. Niepce died before the process was perfected, leaving Daguerre to finesse the technique, name it after himself, and take the first known daguerreotype in 1837. Two years later, the discovery was announced by the French Academy of Sciences, and the French government declared the daguerreotype a “gift to the world.” The photographic process spread quickly and for the first time, photography became a viable profession.
To take a daguerreotype, the photographer uses a polished photographic plate covered in silver iodide. The plate is exposed to light through a camera, and then fumed over warm mercury until the image develops, at which point the image can be fixed. The resulting image is usually reversed, unless the camera is fitted with a mirror, and it is also extremely fragile and sensitive to both light and heat.
Historically, daguerreotypes were sold in glass cases so that the glass could protect the image. Even with a protective glass case, many of these images have been lost over time, although there are a few notable surviving images, such as an early portrait of Abraham Lincoln as a United States Senator. Daguerreotyping also had the distinct disadvantage of being a direct photographic process, making the images impossible to replicate and distribute. Copies of daguerreotypes could be made by engraving, but engravings do not capture the same level of detail that a photograph does.
The daguerreotype proved to be a big hit when it was released to the world. Numerous portrait photography studios sprung up in every major city to cater to people demanding photographs. As the process was refined, the time needed for exposure shrank from 15 to 30 minutes to under a minute, making photography more comfortable and workable for portrait subjects. The introduction of the ambrotype in 1854 effectively pushed the daguerreotype out of fashion, but one could say that the daguerreotype paved the way for modern photography by showing that it was possible to make photography commercially viable.