Negative to Postive Process

The inventor of the first negative from which multiple postive prints were made was Henry Fox Talbot, an English botanist and mathematician and a contemporary of Daguerre.
Talbot sensitized paper to light with a silver salt solution. He then exposed the paper to light. The background became black, and the subject was rendered in gradations of grey. This was a negative image, and from the paper negative, Talbot made contact prints, reversing the light and shadows to create a detailed picture. In 1841, he perfected this paper-negative process and called it a calotype, Greek for beautiful picture.