Film Format

Generally, film has three main formats (or sizes) and these are small, medium and large. The most common small format film size is 35mm and is also known as 135, where the diagonal length of the image is 35mm. All small format film is roll film, which means that it is a long strip of film rolled onto a spool and housed in a light tight cylinder. Other types of small format film include 110 (18mm) and APX films (28mm). The standard number of negatives to each roll is 12, 24 or 36.

Medium format films all use 120 /220 roll film. The standard 2 ¼ film is a 2 ¼ square image area, alternatively known as 6 x 6 format. 120 film gives 12 exposures and 220 film gives 24 exposures. 120 / 220 film also comes in formats of 6 x 4.5 and 7 x 7.

Large format film is referred to as sheet film as each image is on a separate negative. All large format films are measured in inches where the smallest format is 4 x 5 film. The sizes then increase to 5 x 7, 8 x 10, 11 x 14 and 16 x 20. These films obviously can only be used in cameras that can accommodate the film.