[ There are simplified versions of the process that use a combined bleach-fix (]EDTA
Ethylenediaminetetraacetic acid (EDTA), also called EDTA acid, is an aminopolycarboxylic acid with the formula . This white, slightly water-soluble solid is widely used to bind to iron (Fe2+/Fe3+) and calcium ions (Ca2+), forming water-solubl ...
) that dissolves the silver
Silver is a chemical element; it has Symbol (chemistry), symbol Ag () and atomic number 47. A soft, whitish-gray, lustrous transition metal, it exhibits the highest electrical conductivity, thermal conductivity, and reflectivity of any metal. ...
generated by development and removes undeveloped silver halide. These are not used by commercial C-41 processors, and are marketed for home or field use.
Push processing
Similar to black-and-white film processing, the C-41 process can be adjusted to push-process films. Kodak recommends an additional duration of 30 seconds in the developer bath to push certain films by one stop.
Due to the complexity of the film and exacting nature of the process, the results vary widely; as with black-and-white negatives, the process generally results in a negative that is higher in contrast and sometimes higher in grain.
Cross processing
It is also possible to cross-process slide film for the E-6 process
The E-6 process is a chromogenic Photographic processing, photographic process for developing Ektachrome, Fujichrome and other Reversal film, color reversal (also called slide or transparency) photographic film.
Unlike some color reversal process ...
in C-41, which yields negatives with a color shift and stronger saturation. Varying brands and film speeds yield different color shifts producing bright, saturated colors and high contrast. C-41 film also may be processed in E-6, yielding positive images with a strong green cast, caused by the orange mask.
C-41 film can be processed in standard black-and-white chemicals, to produce a monochrome negative image. The negatives will typically be of very low contrast, and cloudy, partly caused by the orange mask.
Black-and-white use
C-41 "chromogenic" black-and-white films
While C-41 is usually considered a color process, Ilford
Ilford is a large List of areas of London, town in East London, England, northeast of Charing Cross. Part of the London Borough of Redbridge, Ilford is within the Ceremonial counties of England, ceremonial county of Greater London. It had a po ...
currently manufactures a " chromogenic" C-41 compatible black-and-white
Black-and-white (B&W or B/W) images combine black and white to produce a range of achromatic brightnesses of grey. It is also known as greyscale in technical settings.
Media
The history of various visual media began with black and white, ...
film, XP2 Super.[ ]Kodak
The Eastman Kodak Company, referred to simply as Kodak (), is an American public company that produces various products related to its historic basis in film photography. The company is headquartered in Rochester, New York, and is incorporated i ...
used to manufacture a similar film, BW400CN, but this was discontinued in August 2014.[ (These should not be confused with regular black-and-white films, which are not compatible with C-41 chemistry.)
These films work like any other C-41 film; development causes dyes to form in the emulsion. Their structure, however, is different. Although they may have multiple layers, all are sensitive to all colors of light, and are designed to produce a black dye. The result is a black-and white image.
The Kodak film has the same orange base as color C-41 films; the base on XP2 is Purple and Fuji films are clear. The orange base on the Kodak film allows them to be printed with correct blacks on standard color printing machines, but this film can be difficult to print on multigrade black-and-white paper, whose contrast is determined by the use of a colored filter during the printing process. Conversely, the clear-based Ilford and Fuji films sometimes results in off-color prints on color paper, but can be optically printed on black-and-white paper, just like any other black-and-white film.
It is often said that prints from these films do not have grain. While they may not appear to have grain, this statement is technically incorrect. On an image from regular black-and-white film, the individual silver particles forming the image are seen as grain. The image on the C-41 films, however, does not contain silver. Instead, C-41 negatives and prints have clouds of dye, causing the resulting image to appear different from that of silver grain.
]
Traditional black-and-white films
While regular black-and-white films are not intended for use with C-41 chemistry, some photographers have used C-41 developer to develop high-contrast black-and-white films (such as traffic surveillance film and Kodak's Technical Pan). This is done in order to lower the contrast. In this application, only a silver image is formed; the bleach step of the C-41 process is not used, as it would destroy the image.
See also
* Chromogenic
* Replenishment (photography)
References
External links
*Koda
process C-41 (color negative) processing manual Z-131
(PDF
Portable document format (PDF), standardized as ISO 32000, is a file format developed by Adobe Inc., Adobe in 1992 to present documents, including text formatting and images, in a manner independent of application software, computer hardware, ...
)
{{Photography
Photographic film processes