K-14 process

K-14 was the developing process for Kodak's Kodachrome transparency film; the last version having been designated Process K-14M. The process differed significantly from its contemporary, the E-6 process, in both complexity and length. Kodachrome film has no integral color couplers; dyes are produced during processing (each color in a separate step) by the reaction of the color couplers with the oxidised developer. Due to declining sales, Kodak discontinued production of all K-14 chemistry in 2009, concurrently with Kodachrome 64 film. Dwayne's Photo, which operated the last K-14 line in the world, discontinued sales on December 30, 2010; the last roll was processed on January 18, 2011. At least one group of photographers has been assessing the possibility of recreating a K-14 line using orphaned hardware and new chemicals.In 2012, photographer Steven Frizza had documented success in reproducing the K-14 process manually, noting its difficulty and expense.

The layers in the film are, top-to-bottom: blue sensitive (yellow), yellow filter, blue-green sensitive (magenta), blue-red sensitive (cyan), acetate base, rem-jet antihalation backing.

The processing cycle is as follows:

The result is three different color records each with the appropriate dye, just like other color films. The original Kodachrome process in 1935 used dye bleaches and was a far more complex process. Although the formulae have changed over the years, the basic process steps have followed a similar pattern since the introduction of "selective re-exposure" Kodachrome in 1938.

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