I was watching the film "I could never be your woman" when I was thinking about the rule of thirds, and the use of composition to create a mood or feeling within a film, and have some examples of the use of composition in this film to create a certain atmosphere:
Above is a scene from a film. It's a comfortable, mildly amusing scene. The frame is laid out very much according to the rule of thirds. Graham Norton and Michelle Pfeiffer are both around the line of thirds on one side of the screen, whilst Paul Rudd fills the negative space in the mirror, creating a sense of balance across the frame. This then transitions round to a new frame shown below:
The balance is kept within the frame, with the three characters evenly spread out across the frame, Graham Norton roughly on one line of thirds, Michelle Pfeiffer the other, and Paul Rudd in between helping to balance out the frame. This still is very comfortable framing, and doesn't do anything to upset the relaxed atmosphere already created.
Above is another scene from later on in the movie. There is an argument going on. The frame is very uneven. No one is quite on a line of third, and the characters are on one side of the frame, leaving a fair bit of negative space between them, and who they are arguing with. This certainly is a more uneasy frame, creating a feeling of tension to go with the argument that is in progress.
The argument is over, but is left without a resolution, and the scene transitions to this frame, with Michelle Pfeiffer on her own. She is positioned slightly off center, but not close enough to a third to still create some tension. It is helping the viewer feel the lack of a resolution from the argument, and the uneasy mood that still lingers with this character.
These are just a couple of examples of composition to create an atmosphere from this film. It was frequent throughout the film. It is certainly a large part of filmmaking, being aware of how composition affects the mood of the piece, and even a simple comedy, such as this film, can benefit greatly from the use of good composition.