Dimensions and specifications of ordinary film

Common films are 120 film and 135 film.

135 film is often used, and 135 film is suitable for various models of 135 cameras. This film is 35 mm wide and 160 ~ 170 cm long. There are holes arranged regularly on both sides of the film. Generally, 36 3.6 cm× 2.4 cm negatives can be taken, and 20, 24 and 72 exposures can also be taken 135.

120 film can take photos of different sizes according to different 120 cameras, including 16 negative (the frame is 4.5× 6 cm); Shoot 12 negative (6× 6 cm); There are also 10 negatives (6×7 cm) and 8 negatives (6×9 cm). The length of 120 film is generally 8 1-82.5cm, and the width is 6.1-6.5cm.120 film. How many negatives are taken depends on the camera model.

Extended data:

the history of film

Movies? , is a kind of material made into images. Now the widely used film is coated with silver halide on the basis of polyacrylate film. This kind of film is soft and easy to roll into a whole roll, so it is also called film. When the light shines on the silver halide, the silver halide turns into black silver, which is fixed on the master after the development process and becomes a common black-and-white negative. Color negative is coated with three layers of silver halide to show three primary colors. In addition to negative films, there are also positive films and primary imaging films.

In the early days, glass was used as the film base. /kloc-in the late 20th century, the technology of plastic industry was mature, and pressed plastic sheets replaced glass as the base.

Films are classified according to their sensitivity (din/ISO), ranging from ISO25 with the lowest speed to ISO3200 with the highest speed. Generally speaking, the lower the sensitivity, the finer the picture quality. The most commonly used film is din2 1 degree /ISO 100, followed by fast film, namely din24 /ISO200. Other speed films, due to the special requirements of price and processing technology, were almost only used by professionals after the rise of digital photography around 2000. However, due to the rise of retro style, movies are slightly popular again.

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