The physical form of popular film has changed over the last 75 years and seems likely to continue to do so. Here we have documented four linear changes. We believe that all of them have been created by filmmakers seeking to control the attention of their viewers, and possibly to enhance viewer involvement in film. These four dimensions—shot length, motion, the coupling of shot length withmotion, and luminance—by nomeans exhaust the potential changes that might be found in popular film over this span, but they do add to our cinemetric knowledge of how films have been constructed and how perceptually relevant variables have been harnessed to produce.
