On board the Type 12 frigate HMS Berwick (1959) alongside the south wall in No.3 basin at Chatham Dockyard, near the end of her modernization which commenced 4 December 1967 and completed 4 June 1971. The photographer is in the sonar control room between 35¼ and 39 stations on the starboard side of 1 deck looking aft and to port from 36½ station showing the senior officer's chair on a raised platform in the centre. The door to the room is on the right and two fire extinguishers are next to it. Terminal boxes and an operator's position are against the port bulkhead. On the aft bulkhead are a Plessey Electronics Sippican unit, a sonar range and bearing unit and other indicator panels. A vertical format negative.