Francis Martin Duncan (1873–1961) was a British naturalist and nature documentary pioneer who worked for producer Charles Urban.

He specialised in micro-cinematography and pioneered many of the techniques of future natural history filmmaking.

In the early 1890s he experimented with chronophotography (sequence photography), showing the results in motion on a Zoetrope.

Together they launched a film series, The Unseen World, showcased at the Alhambra Theatre in London from 17 August 1903, which showed scenes of animal life, with particular emphasis on micro-cinematographic views.

[1] Among the films shown were Circulation of Blood in a Frog's Foot, Red Sludge Worms and the notorious The Cheese Mites, the views of which were preceded by a scene of a man (played by Duncan himself) horrified by what he sees when he views a piece of Stilton through a magnifying glass.