orthochromatic film
Quick Summary
Orthochromatic film is a type of photographic film that is sensitive to all colors of light except red. This means it can capture tones of blue, green, and yellow, but not red. While initially used for general photography, its primary applications now include photographing phosphor screens, such as those on cathode-ray tubes, and other situations where green sensitivity is needed but red sensitivity is not.12
Initially, photographic emulsions were only sensitive to ultraviolet and blue light. Sensitizing dyes were later added to extend sensitivity across the visible spectrum, leading to panchromatic films that record colors as gray tones corresponding to their visual brightness. Orthochromatic films, while not as comprehensive as panchromatic films, were an improvement over non-color-sensitized emulsions.1
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motion-picture technologyIntroduction of colorā¦filter to a bi-pack of orthochromatic and panchromatic films with their emulsion surfaces in contact. The orthochromatic film became the blue record. As it was insensitive to red light, the orthochromatic film passed the red rays to the panchromatic film. A 1938 improvement added red-orange dye to the orthochromatic filmā¦
Read Moreā¦filter to a bi-pack of orthochromatic and panchromatic films with their emulsion surfaces in contact. The orthochromatic film became the blue record. As it was insensitive to red light, the orthochromatic film passed the red rays to the panchromatic film. A 1938 improvement added red-orange dye to the orthochromatic filmā¦
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ā¦and the emulsion was called orthochromatic. Later (1904) dyes were found to prolong the sensitivity into the red, and this emulsion is called panchromatic (Figure 3, curve c). The dates are fairly early for motion-picture application, but the development had importance in the general technology.
Read Moreā¦and the emulsion was called orthochromatic. Later (1904) dyes were found to prolong the sensitivity into the red, and this emulsion is called panchromatic (Figure 3, curve c). The dates are fairly early for motion-picture application, but the development had importance in the general technology.
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technology of photographyColour sensitivityAt one time orthochromatic filmsāsensitive to violet, blue, green, and yellow but not to redāwere also used for general photography; now they are employed mainly for photographing of phosphor screens, such as cathode-ray tubes, and for other purposes requiring green but not red sensitivity.
Read MoreAt one time orthochromatic filmsāsensitive to violet, blue, green, and yellow but not to redāwere also used for general photography; now they are employed mainly for photographing of phosphor screens, such as cathode-ray tubes, and for other purposes requiring green but not red sensitivity.
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