Photogenic Drawing

Leaf of a fern, H.F. Talbot, Schaaf No 138, Image provided by André Jammes 1970, 16 x 11,3 cm, Société française de photographie in The William Henry Fox Talbot catalogue raisonné, Bodleian Libraries

Historical period of production and use

Invented and named in England by William Henry Fox Talbot in 1834, he described it in 1835 as a process for printing multiple positive images, laying the foundations for ‘modern’ photography. Talbot improved his process and in 1841 registered a patent that he called ‘calotype’ (see paper negative notice). The photogenic drawing then became obsolete and was gradually replaced by the calotype, which made it possible to produce negatives using cameras.

Manufacturing

The paper is sensitized using a two-step process: water and table salt (sodium chloride) are first applied, followed by a brushed-on coating of silver nitrate. The resulting silver chloride is not particularly sensitive, which means that the process requires relatively lengthy exposure times. As a result, the first photogenic drawings were obtained through direct contact with flat objects (plants, fabrics, drawings or manuscripts, etc.), following the principle of a photogram. Later on, Talbot experimented with using the same sensitized paper in a camera obscura to capture still life images and architectural silhouettes, including some of his own home at Lacock Abbey.

The negative image was formed by printing out in direct light. It was then stabilized (but not permanently fixed) in an alkaline halide solution (chloride, bromide, or iodide) before the remaining sensitized salts were washed off the paper with water. The lilac, brown, and yellow shades generated by sodium chloride, potassium bromide, or potassium iodide respectively tend to darken over time, making the image relatively unstable when stored in darkness and even more fragile when exposed to light. More stable photogenic drawings were obtained after the introduction of sodium thiosulfate (known originally as hyposulfite of soda) to 'fix' the images, but not before1840.

Credits

Visual Glossary of Photographic Processes © ARCP / Mairie de Paris, 2023