Sidney Cotton's work found only grudging approval with the Royal Air Force, but eventually his work was incorporated into No. 1 Photographic Development Unit (PDU) at RAF Heston and then RAF Benson, a unit from which most later British air reconnaissance developed.
Britain was far behind Germany in optics, and at one time 1 PRU took two Zeiss Ikon cameras with 60 cm lenses from a lost Ju-88 and used them for high-altitude photography [REF].