Impossible colors
Encyclopedia
Impossible colors or forbidden colors are hue
s that cannot be perceived in ordinary viewing conditions from light that is a combination of various intensities of the various frequencies of visible light. Examples of impossible colors are bluish-yellow and reddish-green. This does not mean the muddy brown color created when mixing red and green paints, or the green color from mixing yellow and blue paints, but rather colors that appear to be similar to, for example, both red and green, or both yellow and blue. Other colors never experienced in ordinary viewing, but perceivable under special artificial laboratory conditions, would also be termed impossible colors.
have some overlap in the wavelengths of light to which they respond, so it is more efficient for the visual system to record differences between the responses of cones, rather than each type of cone's individual response. The opponent color theory suggests that there are three opponent channels: red versus green, blue versus yellow, and black versus white (the latter type is achromatic and detects light-dark variation, or luminance). Responses to one color of an opponent channel are antagonistic to those to the other color.
Other researchers dispute the existence of colors forbidden by opponency theory and claim they are, in reality, intermediate colors. See also binocular rivalry
.
author H. P. Lovecraft
wrote a short story called "The Colour Out of Space
" in which a meteorite
crashed into a family farm in rural New England
. The meteorite contained a mysterious globule of a color that was "almost impossible to describe," with a note that it was "only by analogy" that professors studying the globule called it a color at all.
David Lindsay in A Voyage to Arcturus
described ulfire and jale, two colors visible under the sun Alppain: "Just as blue is delicate and mysterious, yellow clear and unsubtle, and red sanguine and passionate, so he felt ulfire to be wild and painful [and] jale [to be] dreamlike, feverish, and voluptuous."
In 1955, the poet Robert Graves
wrote "Welsh Incident," in which something unusual from the sea caves of Criccieth
is described as "mostly nameless colours, colours you'd like to see."
Octarine is Terry Pratchett
's imaginary eighth color, described as a "greenish-yellow purple."
A hoax or spoof recording by Negativland
, featuring the fictional character Crosley Bendix, purports to describe the newly discovered, "fourth primary" color, named "squant."
"hTun" is an impossible color that is "similar to brown" in the book Fairest
, by Gail Carson Levine
.
In episode 4 of the first series of Nebulous
, "Holofile 333: Madness Is a Strange Colour", Vartox Paint Company's new color, Garrow (a sort of yellowy black but with more of a pinky green feel...), is sending people insane.
In "Resurection", the final episode of Futurama's sixth season, the Colorama segment ends with Fry causing a seventh color to appear in a rainbow. While it is shown on-screen, the entire segment is in black & white, so it appears as just another shade of grey to the viewer.
Hue
Hue is one of the main properties of a color, defined technically , as "the degree to which a stimulus can be describedas similar to or different from stimuli that are described as red, green, blue, and yellow,"...
s that cannot be perceived in ordinary viewing conditions from light that is a combination of various intensities of the various frequencies of visible light. Examples of impossible colors are bluish-yellow and reddish-green. This does not mean the muddy brown color created when mixing red and green paints, or the green color from mixing yellow and blue paints, but rather colors that appear to be similar to, for example, both red and green, or both yellow and blue. Other colors never experienced in ordinary viewing, but perceivable under special artificial laboratory conditions, would also be termed impossible colors.
Opponent process
The color opponent process is a color theory that states that the human visual system interprets information about color by processing signals from cones and rods in an antagonistic manner. The three types of conesCone cell
Cone cells, or cones, are photoreceptor cells in the retina of the eye that are responsible for color vision; they function best in relatively bright light, as opposed to rod cells that work better in dim light. If the retina is exposed to an intense visual stimulus, a negative afterimage will be...
have some overlap in the wavelengths of light to which they respond, so it is more efficient for the visual system to record differences between the responses of cones, rather than each type of cone's individual response. The opponent color theory suggests that there are three opponent channels: red versus green, blue versus yellow, and black versus white (the latter type is achromatic and detects light-dark variation, or luminance). Responses to one color of an opponent channel are antagonistic to those to the other color.
Claimed evidence for ability to see impossible colors
In 1983, Hewitt D. Crane and Thomas P. Piantanida carried out tests using a device that had a field of a vertical red stripe adjacent to a vertical green stripe (or in some cases, yellow–blue). In contrast to apparatus used in simpler tests the device had the ability to track involuntary eye movement, and adjust mirrors so that the image would appear to be completely stable. The boundary of the red–green stripes was stabilised on the retina of one eye while the other eye was patched and the field outside the stripes was blanked with occluders. This allowed for a mixing of the two colors in the brain, producing neither green for a yellow–blue test, nor brown for a red green test, but new colors entirely. Some of the volunteers for the experiment even reported that afterwards, they could still imagine the new colors for a period of time.Other researchers dispute the existence of colors forbidden by opponency theory and claim they are, in reality, intermediate colors. See also binocular rivalry
Binocular rivalry
Binocular rivalry is a phenomenon of visual perception in which perception alternates between different images presented to each eye.When one image is presented to one eye and a very different image is presented to the other, instead of the two images being seen superimposed, one image is seen for...
.
Impossible colors in fiction
In 1927, American horror fictionHorror fiction
Horror fiction also Horror fantasy is a philosophy of literature, which is intended to, or has the capacity to frighten its readers, inducing feelings of horror and terror. It creates an eerie atmosphere. Horror can be either supernatural or non-supernatural...
author H. P. Lovecraft
H. P. Lovecraft
Howard Phillips Lovecraft --often credited as H.P. Lovecraft — was an American author of horror, fantasy and science fiction, especially the subgenre known as weird fiction....
wrote a short story called "The Colour Out of Space
The Colour Out of Space
"The Colour Out of Space" is a short story written by American fantasy author H. P. Lovecraft in March 1927. In the tale, an unnamed narrator pieces together the story of an area known by the locals as the "blasted heath" in the wild hills west of Arkham, Massachusetts...
" in which a meteorite
Meteorite
A meteorite is a natural object originating in outer space that survives impact with the Earth's surface. Meteorites can be big or small. Most meteorites derive from small astronomical objects called meteoroids, but they are also sometimes produced by impacts of asteroids...
crashed into a family farm in rural New England
New England
New England is a region in the northeastern corner of the United States consisting of the six states of Maine, New Hampshire, Vermont, Massachusetts, Rhode Island, and Connecticut...
. The meteorite contained a mysterious globule of a color that was "almost impossible to describe," with a note that it was "only by analogy" that professors studying the globule called it a color at all.
David Lindsay in A Voyage to Arcturus
A Voyage to Arcturus
A Voyage to Arcturus is a novel by Scottish writer David Lindsay, first published in 1920. It combines fantasy, philosophy, and science fiction in an exploration of the nature of good and evil and their relationship with existence. It has been described by critic and philosopher Colin Wilson as the...
described ulfire and jale, two colors visible under the sun Alppain: "Just as blue is delicate and mysterious, yellow clear and unsubtle, and red sanguine and passionate, so he felt ulfire to be wild and painful [and] jale [to be] dreamlike, feverish, and voluptuous."
In 1955, the poet Robert Graves
Robert Graves
Robert von Ranke Graves 24 July 1895 – 7 December 1985 was an English poet, translator and novelist. During his long life he produced more than 140 works...
wrote "Welsh Incident," in which something unusual from the sea caves of Criccieth
Criccieth
Criccieth is a town and community on Cardigan Bay, in the Eifionydd area of Gwynedd in Wales. The town lies west of Porthmadog, east of Pwllheli and south of Caernarfon. It has a population of 1,826....
is described as "mostly nameless colours, colours you'd like to see."
Octarine is Terry Pratchett
Terry Pratchett
Sir Terence David John "Terry" Pratchett, OBE is an English novelist, known for his frequently comical work in the fantasy genre. He is best known for his popular and long-running Discworld series of comic fantasy novels...
's imaginary eighth color, described as a "greenish-yellow purple."
A hoax or spoof recording by Negativland
Negativland
Negativland is an experimental music and sound collage band which originated in the San Francisco Bay Area in the late 1970s. They took their name from a Neu! song, while their record label is named after another Neu! song...
, featuring the fictional character Crosley Bendix, purports to describe the newly discovered, "fourth primary" color, named "squant."
"hTun" is an impossible color that is "similar to brown" in the book Fairest
Fairest
Fairest is a 2006 novel by Gail Carson Levine. It is based on the story of Snow White and set in the same world as Ella Enchanted. The kingdom of Ayortha, the setting of the story, is the neighbouring kingdom of Kyrria, where Ella Enchanted was set; as such, several allusions in the story are...
, by Gail Carson Levine
Gail Carson Levine
Gail Carson Levine is an American author of young adult books. Her first novel, Ella Enchanted, received a Newbery Honor in 1998.-Early life:...
.
In episode 4 of the first series of Nebulous
Nebulous
Nebulous is a post apocalyptic science fiction comedy radio show written by Graham Duff and produced by Ted Dowd from Baby Cow Productions; it is directed by Nicholas Briggs. The series premiered in the United Kingdom on BBC Radio 4...
, "Holofile 333: Madness Is a Strange Colour", Vartox Paint Company's new color, Garrow (a sort of yellowy black but with more of a pinky green feel...), is sending people insane.
In "Resurection", the final episode of Futurama's sixth season, the Colorama segment ends with Fry causing a seventh color to appear in a rainbow. While it is shown on-screen, the entire segment is in black & white, so it appears as just another shade of grey to the viewer.