One of the inventors of photography, William Fox Talbot, experimented with contact printing of flowers, ferns and leaves directly on to photographic plates. The history of photography is full of such innovation. In the 1920s a new wave of artists such as Man Ray and Lazlo Moholy-Nagy rediscovered such techniques and took them onto another artistic level.

Often the spur to produce such unconventional, rule-breaking work was a chance "mistake". In the early days of collodion plates, before the invention of photographic paper, the plates were reused, and had to be thoroughly cleaned between exposures. If this was not carried out properly, a double exposure would result, sometimes ruining a careful composition, but occasionally producing a chance work of art.

The making of composite photographs in Victorian times also resulted from the technical deficiencies of the materials available. Landscape photographers would find that it was possible to have the land or the sky properly exposed, but not both, so the practice of taking two exposures and combining them in the darkroom became common. These days we have developed graduated filters to overcome the problem, but out of these early combination prints, photomontage, as we now know it, emerged.

Even with an art form as young as photography, there were the purists who regarded composite works as illegitimate: the French Photographic Society banned them from their exhibitions. Despite this opposition, many good examples of complex combination printing have survived, often with "high art" themes. Tableaux vivants, designed to resemble classical painting, could be made form multiple photographs of the participants, ensuring the required quality, which would have been otherwise impossible.

A variety of methods for making composite photographs was discovered during the Victorian era. The more complex examples were constructed in the darkroom using multiple exposures onto the same plate, with unexposed areas being masked by pieces of black velvet, presaging the precise realism of the likes of John Heartfield, who employed professional photographers to seamlessly blend his ideas in the darkroom.

Other images were produced from a more primitive "cut and paste" technique, and the final picture then rephotographed, an approach to montage that has persisted ever since, and still finds favour with some of today's montage artists like Sean Hillen.

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