Daguerreotype
Invented by Louis-Jacques-Mandé Daguerre and introduced worldwide in 1839, daguerreotype was almost completely superseded by 1860 with new, less expensive processes yielding more readily viewable images. In the late 20th century, there was a revival of daguerreotypy by a small number of photographers interested in making artistic use of early photographic processes.
René Dagron
He grew up in rural France but he left for Paris at an early age. In Paris he distinguished himself in the study of Physics and Chemistry. As a chemistry student Dagron became interested in Daguerrotypes when the process of producing them was announced on 19 August 1839. After graduation, Dagron established a photographic portrait studio in Paris. While in Paris Dagron became familiar with the collodion wet plate and collodio-albumen dry plate processes which he would later adapt to his microfilm techniques.