A simple hand-driven camera mount designed to track the stars; also known as a barn-door mount, or as a Haig mount, after the Scottish physicist and amateur astronomer George Youngson Haig (1928– ), who invented it in 1972. It consists of two boards, hinged at one end, with the hinge aligned parallel with the Earth’s axis and the lower board fixed. The camera is carried on the upper board. A bolt is turned to move the upper board to counteract the Earth’s rotation. The apparatus is suited to short exposures with comparatively wide-angle lenses, its main advantage being cheapness.