A roll film negative. On board the submarine Sealion (1959) towards the end of a long refit at Portsmouth. The photographer is in the gyro compass room between 65 and 68 stations below the main flat, looking down into the starboard forward corner showing the electrical spare gear locker (cupboard three) at the top with an electric magnetic log keel probe unit below it. On the right is the Admiralty gyro compass repeater panel. A vertical format negative.