Daguerreotypes were the earliest public form of photography. They were invented by Louis Daguerre, a French artist, after years of collaborating with Joseph Niépce, an inventor and chemist. Niépce is credited with taking what is considered to be the first photograph, in 1826. The image took at least eight hours of exposure to create and was composed of a view from Niépce's window.
After Niépce's death, Daguerre went on to perfect a process that took much less time to fix an image on a sheet of silver-plated copper. The daguerreotype was announced to the public in 1839.
Since capturing a daguerreotype originally took up to 20 minutes, neck clamps were often used to keep the subject of a portrait still so as not to blur the final image.
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