I was asked about lighting and here are some ideas from BFI.
The Truman Show combines personal drama with an incisive critique of contemporary media. Peter Weir frequently stages action and composes shots so that the real world is imbued with a fantastical and certainly uneasy sense of the overly perfect. The lighting for much of the film is high key, which means the images have a flat, bright quality. It appears almost too perfect and artificial, which as we discover is exactly the situation – the world that Truman inhabits is a television studio set. For those scenes where Truman finds himself challenged by his environment and therefore compelled to question it, the lighting changes. Several key sequences, when issues are raised that Truman has to deal with, occur at night. The film uses a barrelling effect to suggest we are watching some of the action through a hidden camera, for example when Truman goes to cross the water. A barrelling effect is achieved when a wide-angle lens is attached to the camera and the rim of the lens is just about visible at the edge of the frame.