Sheet film
Sheet film ( rare: sheet film ) is a film in leaves, which is not rolled. It is used in large-format cameras (also called sheet film cameras ) and used in pinhole cameras, typically using a sheet film cassette. The Instant Films of Polaroid can be classified in the category of flat films.
Use
Working with sheet film is relatively simple and inexpensive. Sheet film is used mainly for advertising, food, industrial and architectural photography, where many adjustment possibilities and elaborate lighting are needed.
Sheet film is also used in the photo lab to duplicate, reproduce, masking, Tontrennen and copying.
The coated side of a sheet film is characterized by notches in it. The coated side facing the viewer, if he feels the notches at the top right ( in portrait mode ). The film is placed in a film cassette. Then it is closed with a slide. The slider is pulled out only just before the exposure, and then re-inserted. Each film type has its own combination of notches and spikes, so the experienced photographer or assistant can detect the type of film when inserting and removing in the darkroom.
From the 1920s, the medium-format and since the 1930s, the small-format photography were victorious. Since the proliferation of digital photography are for sheet film cameras digital backs, such as Sinar or Linhof offered.
Processing
Sheet film can be processed in own photo lab. Condition are bowls or small tanks of appropriate size; instead of spirals, the devices must be equipped with sheet film holders.
In the professional photo lab print film is processed with special processors in tanks, in which the films are mounted to a frame (tank development).
History and Development
The data used in the early days of photography wet collodion glass plates of the and later the gelatin dry plate were replaced by the celluloid of the brothers Hyatt. Inventor of the photographic sheet film was Hannibal Goodwin. The new substrate was flexible, unbreakable and easy. John Carbutt, Philadelphia, planed in July 1888, if not earlier, flat films of celluloid blocks, which he coated photographically. The celluloid also enabled the production of roll film and motion picture film.
Formats
Sheet film is fabricated in a variety of formats. The formerly very widespread dimensions are:
- 9 cm × 12 cm
- 13 cm × 18 cm
Today, the market is very shrunk, the inch dimensions are the most common:
- 6.5 cm × 9 cm
- 4 " x 5 " (10.16 cm x 12.7 cm)
- 5 " x 7" ( 12.7 cm x 17.78 cm)
- 18 cm × 24 cm
- 8 " x 10 " (20.32 cm x 25.4 cm)
- 11 "× 14" (27.94 cm x 35.56 cm)
In most cases, boxes of 10, 25 or 50 sheet films are offered. The boxes are tripartite and consist of low carton that are plugged into each other. The footage itself is packaged in a frangible light protection cover. The film films mentioned in the margin notches (see photo above), allowing identification of the type of film in the dark.
In sizes from 9 cm × 12 cm to 20.32 cm × 25.4 cm (8 " × 10") is spoken in the photography of large format, about of oversize or ULF (Ultra Large Format. )