DYE DIFFUSION PRINT
It was in 1948 that the American scientist Edwin H. Land developed the first instant picture camera, which he named the Polaroid 95. Until the 1960s, the images it produced were in black and white; it wasn't until 1962 that colour Polaroid films first appeared. In 1972, the Polaroid factory released the SX-70, an instant camera with a completely automatic printing process. Polaroid's simplicity and instantaneousness was an immediate hit with the public and a number of artists, including Andy Warhol and Robert Mappelthorpe. Other brands, such as Kodak
(1976 to 1986), and then Fuji (from 1991), also produced instant picture films.
As with the majority of photographic techniques,
the principle behind instant picture prints involves
the combination of a negative and a positive.
The receiving layer, which becomes the positive,
is pressed against the negative by two rollers inside
the camera. As the positive and the negative pass through these rollers, a pod breaks open, releasing the reagent product, which spreads between the negative
and the positive. The image is then formed from
a transfer/diffusion process. For black and white films, unexposed photosensitive salts are transferred from
the negative to the positive. For colour films, dyes are transferred from one layer to another. A final chemical reaction sets the image so that it can then be viewed
in direct daylight.
There are two different types of film: detachable (peel apart) film and integral film.
In the first case, after exposure, the photographer pulls the film out of the camera. After a minute or so,
the negative is manually separated from the positive
and then disposed of.
In the case of integral films, used from 1972 onwards,
the photo is directly ejected from the camera. There is
no additional manual step as the negative sheet forms
an integral part of the final print. The image, however, does not appear immediately and is only fully visible after a few minutes of processing.
Instant picture prints can be used for other processes too, such as for the transfer of emulsion, where the image layer is separated from the initial support in a bath
of warm water and then placed on a new support, such paper, metal or tissue. The dyes could even be transferred directly to a new type of paper, such as watercolour paper.
In 2007, the Polaroid company announced that it would
no longer be producing film for instant cameras.
In 2008, however, Florian Kaps, creator of the website polaroid.com, in collaboration with Ilford and with
the help of former Polaroid employees, set up
the Impossible Project and successfully re-launched production. This lead to new instant films appearing
on the market in 2010.
Visual glossary of photographic techniques
© ARCP / Mairie de Paris, 2014