Photogravure in the context of W. E. F. Britten

Photographic plates preceded film as the primary medium for capturing images in photography. These plates, made of metal or glass and coated with a light-sensitive emulsion, were integral to early photographic processes such as heliography, daguerreotypes, and photogravure. Glass plates, thinner than standard window glass, became widely used in the late 19th century for their clarity and reliability. Although largely replaced by film during the 20th century, plates continued to be used for specialised scientific and medical purposes until the late 20th century.

Heliography is an early photographic process, based on the hardening of bitumen in sunlight. It was invented by Nicéphore Niépce around 1822. Niépce used the process to make the earliest known surviving photograph from nature, View from the Window at Le Gras (1826 or 1827), and the first realisation of photoresist as means to reproduce artworks through inventions of photolithography and photogravure.

The Latin maxim ignoramus et ignorabimus, meaning "we do not know and will not know", represents the idea that scientific knowledge is limited. It was popularized by Emil du Bois-Reymond, a German physiologist, in his 1872 address "Über die Grenzen des Naturerkennens" ("The Limits of Science").

Count Stanisław Julian Ostroróg (January 1836 – 31 May 1890) was an exiled Polish nobleman and Crimean War veteran. He later became known as an early professional portrait photographer who created photogravures, under the professional name of Walery, of many notable contemporaries, including Queen Alexandra of Denmark, Queen Victoria, Victor Hugo, and Sarah Bernhardt.

After his death, his brand, "Walery", was continued by his eldest son, Stanisław Julian Ignacy Ostroróg in London and Paris, sometimes also as "Lucien Walery" and a range of other related pseudonyms.

William Henry Fox Talbot (/tælbət/; 11 February 1800 – 17 September 1877) was an English scientist, inventor, and photography pioneer who invented the salted paper and calotype processes, precursors to photographic processes of the later 19th and 20th centuries. His work in the 1840s on photomechanical reproduction led to the creation of the photoglyphic engraving process, the precursor to photogravure. He was the holder of a controversial patent that affected the early development of commercial photography in Britain. He was also a noted photographer who contributed to the development of photography as an artistic medium. He published The Pencil of Nature (1844–1846), which was illustrated with original salted paper prints from his calotype negatives and made some important early photographs of Oxford, Paris, Reading, and York.

A polymath, Talbot was elected to the Royal Society in 1831 for his work on the integral calculus, and researched in optics, chemistry, electricity and other subjects such as etymology, the decipherment of cuneiform, and ancient history.