With the advent of photographic emulsions on glass came the potential to make enlargements from them, but for the lack of a sufficiently strong light source to project them on to the receiving emulsion as prints on paper, canvas or other supports. The solar camera, employing the focussed light of the sun, addressed the problem in a repurposing of the solar microscope by American portrait artist David Acheson Woodward in 1857, and others, before being superseded by enlargers employing artificial light sources from the 1880s. Life-size portraits made by this means were hand coloured in crayon or overpainted in oils and were popular into the 1910s.