The process of perforation occurs shortly after the film is manufactured and before the film is exposed. The procedure must be executed in a dark room with only the dim light of a ruby lamp because the raw film is extremely sensitive to light. Therefore, the machines are quite simple to operate due to the impaired vision of the operator. The machines must also puncture the film with exceptional precision because the gauge is determined by the apparatuses, such as Edison’s cinematograph, with teeth that engage the evenly spaced holes. The perforation is not completed by the film manufacturer because it could experience subtle yet significant physical changes under varying climatic conditions while in storage.