Sir Hugh Lyon Playfair (20 February 1787 – 19 January 1861) was a Scottish politician, soldier and photographic pioneer. He was Provost of St Andrews from 1842 to 1861.
Playfair took a strong interest in photography during its pioneer years and worked with Sir David Brewster to develop the calotype process. Though not a member Playfair was one of the founders of the Edinburgh Calotype Club one of the world's first photographic societies (1843).
He was also a keen cellist.
He was born in Meigle in Perthshire the third son of the Reverend James Playfair and Margaret Lyon. He was educated at Dundee Grammar School.
His later education was at the University of St Andrews. He was commissioned in 1804 into the Bengal Horse Artillery. After his commission he was sent to the University of Edinburgh for three months for instruction in range-finding and ballistics. He served in India from 1805 to 1817 and from 1820 to 1834. He was initially based in Calcutta but in November 1806 had to undertake an 800-mile march with his brigade to Cawnpore. In March 1807 General Sir John Horsford placed him in charge of the troops at Bareilly and was required to suppress the robber-chief Tumon Singh in Oudh. In November 1807 he was appointed in charge of the horse artillery in Agra and in 1809 undertook another very long march to Saharunpoor. In 1811 he was moved to Meerut and required to oversee the siege of the fortress at Nalapani. He was twice wounded during the siege but successfully captured the fortress.
Owing to ill-health he was sent back to Britain to recover. His ship moored at St. Helena en-route and he was privileged to meet and interview Napoleon. His second period of duty in India was much less eventful.