Photochromy
Encyclopedia
Photochromy is the art or process of reproducing colors by photography
.[Note] Not to be confused with Photochromism (a reversible color change induced by light energy). See Photochromism
. Furthermore, a Photochrom
is not the result of the photochromy process.
Color printing method by the bleach-out process.
Photography
Photography is the art, science and practice of creating durable images by recording light or other electromagnetic radiation, either electronically by means of an image sensor or chemically by means of a light-sensitive material such as photographic film...
.[Note] Not to be confused with Photochromism (a reversible color change induced by light energy). See Photochromism
Photochromism
Photochromism is the reversible transformation of a chemical species between two forms by the absorption of electromagnetic radiation, where the two forms have different absorption spectra. Trivially, this can be described as a reversible change of colour upon exposure to light...
. Furthermore, a Photochrom
Photochrom
Photochrom"Photochrom" is the spelling used by the Library of Congress, for historical reasons, in its classification and description of its collection of such images. Variants of the spelling exist, both in English and in German. "Photochrome" is the English spelling used in some contexts, e.g....
is not the result of the photochromy process.
History
Colored images by direct exposure from nature using a Lippmann plateLippmann plate
Gabriel Lippmann conceived a two-step method to record and reproduce colours, known as:* direct photochromes,* interference photochromes,* Lippmann photochromes,* Photography in natural colours by direct exposure in the camera...
Color printing method by the bleach-out process.