Sketch made using a camera obscura or camera lucida by English pioneer of photography William Henry Fox Talbot (1800-1877). Talbot invented the first negative/positive proces for producing photographs between 1835 and 1839. For the first time, any number of prints could be made of the same image by transferring the negative image on to special paper to make a positive print. This proces became known as the calotype proces.
© National Museum of Science & Media / Science & Society Picture Library