Roll film

The roll film was invented by Eastman Kodak, and was the prime factor in making photography available for the common man.

In producing roll film, photographic film is rolled onto a single wood, metal or plastic bobbin with a protective outer backing paper.

Due to the backing paper being non-translucent, the photographer may load the film into the camera in subdued daylight. As images are taken, exposed film is rolled over to an identical but initially empty receiving bobbin. For cameras with simple advance mechanisms, most roll film formats have frame number markings printed on the backing paper, visible through a red window at the rear of the camera. When all images are exposed, the film is not rewound. Instead, the now empty bobbin is moved ready to become the receiver of the next roll of film.