The Thornton-Pickard Mark III Hythe Camera (MK III H) is an aerial gun camera built in the form of a machine gun, used to train aircrew in aerial gunnery during the First World War era. It exposed photographic plates rather than firing, allowing instructors to assess a trainee's aim against another aircraft.

With only a single UK auction record to reference, pricing guidance for 2026 is thin: one example fetched £562 at saleroom level in April 2022. That hammer figure suggests a Mark III Hythe in honest, complete condition can be worth several hundred pounds today, though militaria and photographica collectors price these heavily on completeness, maker's markings and original finish, so a tatty example would sell for considerably less and a pristine one materially more.