Misplaced Pages

#738261

114-516: The flag has a white background with two blue diagonal bands, forming a saltire , called St. Andrew's Cross. The ratio of the flag's width to its length is 1 / 1.5, the width of the blue band is 1 / 10 the length of the flag. The Guard Ribbon and image of order awarded to the ship can be added to the flag. In 1698 Peter I the Great established the first Russian medal, the Order of St Andrew , which

228-403: A gamut of colors . This is the essential method used to create the perception of a broad range of colors in, e.g., electronic displays, color printing, and paintings. Perceptions associated with a given combination of primary colors can be predicted by an appropriate mixing model (e.g., additive , subtractive ) that reflects the physics of how light interacts with physical media, and ultimately

342-515: A French chemist, Louis Jacques Thénard , made a synthetic cobalt blue pigment which became immensely popular with painters. In 1824 the Societé pour l'Encouragement d'Industrie in France offered a prize for the invention of an artificial ultramarine which could rival the natural colour made from lapis lazuli. The prize was won in 1826 by a chemist named Jean Baptiste Guimet, but he refused to reveal

456-462: A dark brown. From the Renaissance onward, painters used this system to create their colours (see RYB colour model ). The RYB model was used for colour printing by Jacob Christoph Le Blon as early as 1725. Later, printers discovered that more accurate colours could be created by using combinations of cyan, magenta, yellow, and black ink, put onto separate inked plates and then overlaid one at

570-480: A deep blue colour, was once employed in medieval years, but it is unstable pigment, losing its colour especially under dry conditions. Lapis lazuli , mined in Afghanistan for more than three thousand years, was used for jewelry and ornaments, and later was crushed and powdered and used as a pigment. The more it was ground, the lighter the blue colour became. Natural ultramarine , made by grinding lapis lazuli into

684-705: A fine powder, was the finest available blue pigment in the Middle Ages and the Renaissance . It was extremely expensive, and in Italian Renaissance art, it was often reserved for the robes of the Virgin Mary . Intense efforts have focused on blue flowers and the possibility that natural blue colourants could be used as food dyes. Commonly, blue colours in plants are anthocyanins : "the largest group of water-soluble pigments found widespread in

798-588: A large color triangle ( gamut ). The exact colors chosen for additive primaries are a compromise between the available technology (including considerations such as cost and power usage) and the need for large chromaticity gamut. For example, in 1953 the NTSC specified primaries that were representative of the phosphors available in that era for color CRTs . Over decades, market pressures for brighter colors resulted in CRTs using primaries that deviated significantly from

912-488: A larger gamut of colors via mixing, the blue and red pigments used in illustrative materials such as the Color Mixing Guide in the image are often closer to peacock blue (a blue-green or cyan ) and carmine (or crimson or magenta ) respectively. Printers traditionally used inks of such colors, known as "process blue" and "process red", before modern color science and the printing industry converged on

1026-420: A lower frequency and a longer wavelength gradually appear more green. Purer blues are in the middle of this range, e.g., around 470 nanometres. Isaac Newton included blue as one of the seven colours in his first description of the visible spectrum . He chose seven colours because that was the number of notes in the musical scale, which he believed was related to the optical spectrum. He included indigo ,

1140-546: A match. The negative tristimulus values made certain types of calculations difficult, so the CIE put forth new color matching functions x ¯ ( λ ) {\displaystyle {\overline {x}}(\lambda )} , y ¯ ( λ ) {\displaystyle {\overline {y}}(\lambda )} , and z ¯ ( λ ) {\displaystyle {\overline {z}}(\lambda )} defined by

1254-463: A more complete list see the List of colours ). In nature, many blue phenomena arise from structural colouration , the result of interference between reflections from two or more surfaces of thin films , combined with refraction as light enters and exits such films. The geometry then determines that at certain angles, the light reflected from both surfaces interferes constructively, while at other angles,

SECTION 10

#1732771719739

1368-594: A partitive way to generate color images. Importantly, unlike additive mixture, the color of the mixture is not well predicted by the colors of the individual dyes or inks. The typical number of inks in such a printing process is 3 (CMY) or 4 ( CMYK ), but can commonly range to 6 (e.g., Pantone hexachrome ). In general, using fewer inks as primaries results in more economical printing but using more may result in better color reproduction. Cyan (C), magenta (M), and yellow (Y) are good chromatic subtractive primaries in that filters with those colors can be overlaid to yield

1482-468: A quick-drying binding agent, such as egg yolk ( tempera painting ); or with a slow-drying oil, such as linseed oil , for oil painting . Two inorganic but synthetic blue pigments are cerulean blue (primarily cobalt(II) stanate: Co 2 SnO 4 ) and Prussian blue (milori blue: primarily Fe 7 (CN) 18 ). The chromophore in blue glass and glazes is cobalt (II). Diverse cobalt(II) salts such as cobalt carbonate or cobalt(II) aluminate are mixed with

1596-552: A slight mixture of other colours; azure contains some green, while ultramarine contains some violet. The clear daytime sky and the deep sea appear blue because of an optical effect known as Rayleigh scattering . An optical effect called the Tyndall effect explains blue eyes . Distant objects appear more blue because of another optical effect called aerial perspective . Blue has been an important colour in art and decoration since ancient times. The semi-precious stone lapis lazuli

1710-429: A small initial set of primaries and do not use mathematical modeling. MacEvoy explains why artists often chose a palette closer to RYB than to CMY: Because the 'optimal' pigments in practice produce unsatisfactory mixtures; because the alternative selections are less granulating, more transparent, and mix darker values; and because visual preferences have demanded relatively saturated yellow to red mixtures, obtained at

1824-461: A specific set of pigments that are considered primary colors – the choice of pigments depends entirely on the artist's subjective preference of subject and style of art, as well as material considerations like lightfastness and mixing behavior. A variety of limited palettes have been employed by artists for their work. The color of light (i.e., the spectral power distribution) reflected from illuminated surfaces coated in paint mixes

1938-635: A surprisingly large chromaticity gamut. A black (K) ink (from the older " key plate ") is also used in CMYK systems to augment C, M and Y inks or dyes: this is more efficient in terms of time and expense and less likely to introduce visible defects. Before the color names cyan and magenta were in common use, these primaries were often known as blue and red, respectively, and their exact color has changed over time with access to new pigments and technologies. Organizations such as Fogra , European Color Initiative and SWOP publish colorimetric CMYK standards for

2052-475: A time onto paper. This method could produce almost all the colours in the spectrum with reasonable accuracy. On the HSV colour wheel , the complement of blue is yellow ; that is, a colour corresponding to an equal mixture of red and green light. On a colour wheel based on traditional colour theory ( RYB ) where blue was considered a primary colour, its complementary colour is considered to be orange (based on

2166-452: A very similar sense as Boyle used primary . Moses Harris , an entomologist and engraver, also describes red, yellow, and blue as "primitive" colors in 1766. Léonor Mérimée described red, yellow, and blue in his book on painting (originally published in French in 1830) as the three simple/primitive colors that can make a "great variety" of tones and colors found in nature. George Field ,

2280-426: A yellowish green or a yellowish red) but not within a pair (i.e., reddish green cannot be imagined). An achromatic opponent process along black and white is also part of Hering's explanation of color perception. Hering asserted that we did not know why these color relationships were true but knew that they were. Although there is a great deal of evidence for the opponent process in the form of neural mechanisms, there

2394-665: Is incomplete in that it cannot reproduce every color within the gamut of the standard observer. Practical color spaces such as sRGB and scRGB are typically (at least partially) defined in terms of linear transformations from CIE XYZ, and color management often uses CIE XYZ as a middle point for transformations between two other color spaces. Most color spaces in the color-matching context (those defined by their relationship to CIE XYZ) inherit its three-dimensionality. However, more complex color appearance models like CIECAM02 require extra dimensions to describe colors appear under different viewing conditions. The opponent process

SECTION 20

#1732771719739

2508-667: Is based on descriptions in Colorimetry - Understanding The CIE System . The CIE 1931 standard observer is derived from experiments in which participants observe a foveal secondary bipartite field with a dark surround. Half of the field is illuminated with a monochromatic test stimulus (ranging from 380 nm to 780 nm) and the other half is the matching stimulus illuminated with three coincident monochromatic primary lights: 700 nm for red (R), 546.1 nm for green (G), and 435.8 nm for blue (B). These primaries correspond to CIE RGB color space . The intensities of

2622-450: Is based on experience with pigments, more than on the science of light. In 1920, Snow and Froehlich explained: It does not matter to the makers of dyes if, as the physicist says, red light and green light in mixture make yellow light, when they find by experiment that red pigment and green pigment in mixture produce gray. No matter what the spectroscope may demonstrate regarding the combination of yellow rays of light and blue rays of light,

2736-551: Is currently no clear mapping of the psychological primaries to neural correlates . The psychological primaries were applied by Richard S. Hunter as the primaries for Hunter L,a,b colorspace that led to the creation of CIELAB . The Natural Color System is also directly inspired by the psychological primaries. Philosophical writing from ancient Greece has described notions of primary colors, but they can be difficult to interpret in terms of modern color science. Theophrastus (c. 371–287 BCE) described Democritus ' position that

2850-534: Is no one set of primaries that can be considered the canonical set. Primary pigments or light sources are selected for a given application on the basis of subjective preferences as well as practical factors such as cost, stability, availability etc. The concept of primary colors has a long, complex history. The choice of primary colors has changed over time in different domains that study color. Descriptions of primary colors come from areas including philosophy, art history, color order systems, and scientific work involving

2964-404: Is no plausible way that those primary colors could be represented physically, or perceived). Phenomenological accounts of primary colors, such as the psychological primaries, have been used as the conceptual basis for practical color applications even though they are not a quantitative description in and of themselves. Sets of color space primaries are generally arbitrary , in the sense that there

3078-481: Is no single word for blue, but rather different words for light blue ( голубой , goluboj ; Celeste ) and dark blue ( синий , sinij ; Azul ) (see Colour term ). Several languages, including Japanese and Lakota Sioux , use the same word to describe blue and green. For example, in Vietnamese , the colour of both tree leaves and the sky is xanh . In Japanese, the word for blue ( 青 , ao )

3192-496: Is not well approximated by a subtractive or additive mixing model. Color predictions that incorporate light scattering effects of pigment particles and paint layer thickness require approaches based on the Kubelka–Munk equations , but even such approaches are not expected to predict the color of paint mixtures precisely due to inherent limitations. Artists typically rely on mixing experience and "recipes" to mix desired colors from

3306-399: Is now the blue of blue jeans. As the pace of organic chemistry accelerated, a succession of synthetic blue dyes were discovered including Indanthrone blue , which had even greater resistance to fading during washing or in the sun, and copper phthalocyanine . Woad and true indigo were once used but since the early 1900s, all indigo is synthetic. Produced on an industrial scale, indigo

3420-602: Is often used for colours that English speakers would refer to as green, such as the colour of a traffic signal meaning "go". In Lakota, the word tȟó is used for both blue and green, the two colours not being distinguished in older Lakota (for more on this subject, see Blue–green distinction in language ). Linguistic research indicates that languages do not begin by having a word for the colour blue. Colour names often developed individually in natural languages, typically beginning with black and white (or dark and light), and then adding red , and only much later – usually as

3534-592: Is representative of those results. Matching was performed across many participants in incremental steps along the range of test stimulus wavelengths (380 nm to 780 nm) to ultimately yield the color matching functions: r ¯ ( λ ) {\displaystyle {\overline {r}}(\lambda )} , g ¯ ( λ ) {\displaystyle {\overline {g}}(\lambda )} and b ¯ ( λ ) {\displaystyle {\overline {b}}(\lambda )} that represent

Ensign of the Russian Navy - Misplaced Pages Continue

3648-552: Is still used today. Blue Blue is one of the three primary colours in the RYB colour model (traditional colour theory), as well as in the RGB (additive) colour model . It lies between violet and cyan on the spectrum of visible light . The term blue generally describes colours perceived by humans observing light with a dominant wavelength that's between approximately 450 and 495  nanometres . Most blues contain

3762-568: Is the blue chromophore in stained glass windows , such as those in Gothic cathedrals and in Chinese porcelain beginning in the Tang dynasty . Copper(II) (Cu ) also produces many blue compounds, including the commercial algicide copper(II) sulfate (CuSO 4 5H 2 O). Similarly, vanadyl salts and solutions are often blue, e.g. vanadyl sulfate . When sunlight passes through the atmosphere,

3876-646: Is the blue of blue jeans. Blue dyes are organic compounds, both synthetic and natural. For food, the triarylmethane dye Brilliant blue FCF is used for candies. The search continues for stable, natural blue dyes suitable for the food industry. Various raspberry -flavoured foods are dyed blue. This was done to distinguish strawberry , watermelon and raspberry -flavoured foods. The company ICEE used Blue No. 1 for their blue raspberry ICEEs. Blue pigments were once produced from minerals, especially lapis lazuli and its close relative ultramarine . These minerals were crushed, ground into powder, and then mixed with

3990-686: Is the colour of light between violet and cyan on the visible spectrum . Hues of blue include indigo and ultramarine , closer to violet; pure blue, without any mixture of other colours; Azure, which is a lighter shade of blue, similar to the colour of the sky; Cyan, which is midway in the spectrum between blue and green , and the other blue-greens such as turquoise , teal , and aquamarine . Blue also varies in shade or tint; darker shades of blue contain black or grey, while lighter tints contain white. Darker shades of blue include ultramarine, cobalt blue , navy blue , and Prussian blue ; while lighter tints include sky blue , azure , and Egyptian blue (for

4104-487: Is to be awarded for military exploits and public service. When he became tsar , he started to devise a flag for the Russian Navy . The symbolism of the flag is a tribute to his father, Alexei Mikhailovich Romanov , who established a special flag for the first Russian naval ship , the three-masted frigate Oryol . In 1699 on the draft of the tsar's instruction to Yemelyan Ukraintsev concerning protocol issues of

4218-614: The Baltic Sea area and Northern Europe , and are also found in Eastern , Central , and Southern Europe . Blue eyes are also found in parts of Western Asia , most notably in Afghanistan , Syria , Iraq , and Iran . In Estonia , 99% of people have blue eyes. In Denmark in 1978, only 8% of the population had brown eyes, though through immigration, today that number is about 11%. In Germany , about 75% have blue eyes. In

4332-573: The Caucasus , and as far away as Mauritania . It was used in the funeral mask of Tutankhamun (1341–1323 BC). A term for Blue was relatively rare in many forms of ancient art and decoration, and even in ancient literature. The Ancient Greek poets described the sea as green, brown or "the colour of wine". The colour is mentioned several times in the Hebrew Bible as ' tekhelet '. Reds, blacks, browns, and ochres are found in cave paintings from

4446-470: The Munsell colour wheel ). In 1993, high-brightness blue LEDs were demonstrated by Shuji Nakamura of Nichia Corporation . In parallel, Isamu Akasaki and Hiroshi Amano of Nagoya University were working on a new development which revolutionized LED lighting. Nakamura was awarded the 2006 Millennium Technology Prize for his invention. Nakamura, Hiroshi Amano and Isamu Akasaki were awarded

4560-833: The Nobel Prize in Physics in 2014 for the invention of an efficient blue LED. Lasers emitting in the blue region of the spectrum became widely available to the public in 2010 with the release of inexpensive high-powered 445–447 nm laser diode technology. Previously the blue wavelengths were accessible only through DPSS which are comparatively expensive and inefficient, but still widely used by scientists for applications including optogenetics , Raman spectroscopy , and particle image velocimetry , due to their superior beam quality. Blue gas lasers are also still commonly used for holography , DNA sequencing , optical pumping , among other scientific and medical applications. Blue

4674-539: The Tyndall scattering of light in the stroma, an optical effect similar to what accounts for the blueness of the sky. The irises of the eyes of people with blue eyes contain less dark melanin than those of people with brown eyes, which means that they absorb less short-wavelength blue light, which is instead reflected out to the viewer. Eye colour also varies depending on the lighting conditions, especially for lighter-coloured eyes. Blue eyes are most common in Ireland,

Ensign of the Russian Navy - Misplaced Pages Continue

4788-446: The cone cells . A color model is an abstract model intended to describe the ways that colors behave, especially in color mixing . Most color models are defined by the interaction of multiple primary colors. Since most humans are trichromatic , color models that want to reproduce a meaningful portion of a human's perceptual gamut must use at least three primaries. More than three primaries are allowed, for example, to increase

4902-532: The imagination , cold , and sadness . The modern English word blue comes from Middle English bleu or blewe , from the Old French bleu , a word of Germanic origin, related to the Old High German word blao (meaning 'shimmering, lustrous'). In heraldry , the word azure is used for blue . In Russian , Spanish, Mongolian , Irish , and some other languages, there

5016-402: The iridophore cells in some fish and frogs. Blue eyes do not actually contain any blue pigment. Eye colour is determined by two factors: the pigmentation of the eye's iris and the scattering of light by the turbid medium in the stroma of the iris . In humans, the pigmentation of the iris varies from light brown to black. The appearance of blue, green, and hazel eyes results from

5130-425: The mandarin fish and the picturesque dragonet . More commonly, blueness in animals is a structural colouration ; an optical interference effect induced by organized nanometre-sized scales or fibres. Examples include the plumage of several birds like the blue jay and indigo bunting , the scales of butterflies like the morpho butterfly , collagen fibres in the skin of some species of monkey and opossum , and

5244-894: The retina . The most common color mixing models are the additive primary colors (red, green, blue) and the subtractive primary colors (cyan, magenta, yellow). Red, yellow and blue are also commonly taught as primary colours , despite some criticism due to its lack of scientific basis. Primary colors can also be conceptual (not necessarily real), either as additive mathematical elements of a color space or as irreducible phenomenological categories in domains such as psychology and philosophy . Color space primaries are precisely defined and empirically rooted in psychophysical colorimetry experiments which are foundational for understanding color vision . Primaries of some color spaces are complete (that is, all visible colors are described in terms of their primaries weighted by nonnegative primary intensity coefficients) but necessarily imaginary (that is, there

5358-418: The sRGB primaries fall within the gamut of human perception, and so can be easily represented by practical light sources, including CRT and LED displays, hence why sRGB is still the color space of choice for digital displays. A color in a color space is defined as a combination of its primaries, where each primary must give a non-negative contribution. Any color space based on a finite number of real primaries

5472-410: The 1840s. Thomas Young proposed red, green, and violet as the three primary colors, while James Clerk Maxwell favored changing violet to blue. Hermann von Helmholtz proposed "a slightly purplish red, a vegetation-green, slightly yellowish, and an ultramarine-blue" as a trio. Newton, Young, Maxwell, and Helmholtz were all prominent contributors to "modern color science" that ultimately described

5586-790: The Islamic world, blue was the colour worn by Christians and Jews, because only Muslims were allowed to wear white and green. In the art and life of Europe during the early Middle Ages , blue played a minor role. This changed dramatically between 1130 and 1140 in Paris, when the Abbe Suger rebuilt the Saint Denis Basilica . Suger considered that light was the visible manifestation of the Holy Spirit. He installed stained glass windows coloured with cobalt , which, combined with

5700-969: The L-, M-, and S-cones respectively. A real primary that stimulates only the M-cone is impossible, and therefore these primaries are imaginary. The LMS color space has significant physiological relevance as these three photoreceptors mediate trichromatic color vision in humans. Both XYZ and LMS color spaces are complete since all colors in the gamut of the standard observer are contained within their color spaces. Complete color spaces must have imaginary primaries, but color spaces with imaginary primaries are not necessarily complete (e.g. ProPhoto RGB color space ). Color spaces used in color reproduction must use real primaries that can be reproduced by practical sources, either lights in additive models, or pigments in subtractive models. Most RGB color spaces have real primaries, though some maintain imaginary primaries. For example, all

5814-655: The Romans, blue was the colour of mourning, as well as the colour of barbarians. The Celts and Germans reportedly dyed their faces blue to frighten their enemies, and tinted their hair blue when they grew old. The Romans made extensive use of indigo and Egyptian blue pigment, as evidenced, in part, by frescos in Pompeii . The Romans had many words for varieties of blue, including caeruleus , caesius , glaucus , cyaneus , lividus , venetus , aerius , and ferreus , but two words, both of foreign origin, became

SECTION 50

#1732771719739

5928-547: The Russian embassy to the Ottoman Empire there is a white-blue-red three-striped flag crossed by a diagonal blue St. Andrew 's cross. In 1700 the flags of admiral (white), vice admiral (blue) and counter admiral (red) were introduced; in the canton (the shaft's upper corner) placed the image of St. Andrew's flag on a three-striped background. Officially, the right of Russian warships to fly St. Andrew's flag

6042-558: The United States and Europe, blue is the colour that both men and women are most likely to choose as their favourite, with at least one recent survey showing the same across several other countries, including China, Malaysia, and Indonesia. Past surveys in the US and Europe have found that blue is the colour most commonly associated with harmony , confidence , masculinity , knowledge , intelligence , calmness , distance , infinity ,

6156-417: The United States, as of 2006, 1 out of every 6 people, or 16.6% of the total population, and 22.3% of the white population , have blue eyes, compared with about half of Americans born in 1900, and a third of Americans born in 1950. Blue eyes are becoming less common among American children . In the US, males are 3–5% more likely to have blue eyes than females. As early as the 7th millennium BC , lapis lazuli

6270-722: The Upper Paleolithic period, but not blue. Blue was also not used for dyeing fabric until long after red, ochre, pink, and purple. This is probably due to the perennial difficulty of making blue dyes and pigments. On the other hand, the rarity of blue pigment made it even more valuable. The earliest known blue dyes were made from plants – woad in Europe, indigo in Asia and Africa, while blue pigments were made from minerals, usually either lapis lazuli or azurite , and required more. Blue glazes posed still another challenge since

6384-400: The above equation is known as a tristimulus value and measures amounts in the adopted units. No set of real primary lights can match another monochromatic light under additive mixing so at least one of the color matching functions is negative for each wavelength. A negative tristimulus value corresponds to that primary being added to the test stimulus instead of the matching stimulus to achieve

6498-402: The actual practice of painting. Nonetheless, it has long been known that limited palettes consisting of a small set of pigments are sufficient to mix a diverse gamut of colors. The set of pigments available to mix diverse gamuts of color (in various media such as oil , watercolor , acrylic , gouache , and pastel ) is large and has changed throughout history. There is no consensus on

6612-418: The blue wavelengths are scattered more widely by the oxygen and nitrogen molecules, and more blue comes to our eyes. This effect is called Rayleigh scattering , after Lord Rayleigh and confirmed by Albert Einstein in 1911. The sea is seen as blue for largely the same reason: the water absorbs the longer wavelengths of red and reflects and scatters the blue, which comes to the eye of the viewer. The deeper

6726-624: The cantons of naval flags. In 1712, the final version of the ensign for the fleet's main forces (the middle part of the squadron ) and ships in solo voyage — St. Andrew's flag of white colour with a blue (cyan) cross reaching to the cloth's corners was adopted. From 1692 to 1712 Peter I personally drew eight proposed flags that have consistently been taken into the Navy . Description of the flag's final version by Peter I: Original Text ( Orthography and font (ru) are also original): Modern Russian: Blue and red flags with St. Andrew's flag in

6840-404: The cantons were abolished in 1732–43, 1764–97 (finally abolished in 1865). In 1819 St. George's ensign was established as a reward flag — St. Andrew's flag with the image of St. George placed on a red shield in the centre. It was awarded to the line ship Azov (1827) and the brig Mercurii (1829). In 1837 St. George's flag was introduced for naval crews. St. Andrew's flag was cancelled by

6954-403: The closest to primary colors for its Art & Graphic color pencils range. "Cadmium yellow" (number 107) for yellow, "Phthalo blue" (number 110) for blue and "Pale geranium lake" (number 121) for red, are provided as primary colors in its basic 5 color "Albrecht Dürer" watercolor marker set. The first known use of red, yellow, and blue as "simple" or "primary" colors, by Chalcidius , ca. AD 300,

SECTION 60

#1732771719739

7068-492: The color matching context such as the match being in the foveal field of view, under appropriate luminance, etc. Additive mixing of coincident spot lights was applied in the experiments used to derive the CIE 1931 colorspace (see color space primaries section ). The original monochromatic primaries of the wavelengths of 435.8 nm ( violet ), 546.1 nm ( green ), and 700 nm (red) were used in this application due to

7182-492: The color matching functions, along with data from other experiments, to ultimately yield the cone fundamentals : l ¯ ( λ ) {\displaystyle {\overline {l}}(\lambda )} , m ¯ ( λ ) {\displaystyle {\overline {m}}(\lambda )} and s ¯ ( λ ) {\displaystyle {\overline {s}}(\lambda )} . These functions correspond to

7296-432: The convenience they afforded to the experimental work. Small red, green, and blue elements (with controllable brightness) in electronic displays mix additively from an appropriate viewing distance to synthesize compelling colored images. This specific type of additive mixing is described as partitive mixing . Red, green, and blue light are popular primaries for partitive mixing since primary lights with those hues provide

7410-864: The decree of the All-Russian Congress of the Navy of 18 November (1 December) 1917. During the Russian Civil War St. Andrew's flag was hoisted on the White Navy's ships. After the Russian Revolution , the Russian Navy Ensign was changed, but it was used by the White Army up to 1924. The flag of St Andrew was reintroduced in the Russian Navy in 1992 by the decree of Boris Yeltsin from 21 July, and

7524-463: The early blue dyes and pigments were not thermally robust. In c.  2500 BC , the blue glaze Egyptian blue was introduced for ceramics, as well as many other objects. The Greeks imported indigo dye from India, calling it indikon, and they painted with Egyptian blue. Blue was not one of the four primary colours for Greek painting described by Pliny the Elder (red, yellow, black, and white). For

7638-410: The expense of relatively dull green and purple mixtures. Artists jettisoned 'theory' to obtain the best color mixtures in practice. A color space is a subset of a color model , where the primaries have been defined, either directly as photometric spectra, or indirectly as a function of other color spaces. For example, sRGB and Adobe RGB are both color spaces based on the RGB color model . However,

7752-482: The fact remains that yellow pigment mixed with the blue pigment produces green pigment. The widespread adoption of teaching of RYB as primary colors in post-secondary art schools in the twentieth century has been attributed to the influence of the Bauhaus , where Johannes Itten developed his ideas on color during his time there in the 1920s, and of his book on color published in 1961. In discussing color design for

7866-562: The five primary colors (white, yellow, red, blue, black) was influenced by Aristotle's idea of the chromatic colors being made of black and white. The 20th century philosopher Ludwig Wittgenstein explored color-related ideas using red, green, blue, and yellow as primary colors. Isaac Newton used the term "primary color" to describe the colored spectral components of sunlight. A number of color theorists did not agree with Newton's work. David Brewster advocated that red, yellow, and blue light could be combined into any spectral hue late into

7980-709: The following linear transformation : These new color matching functions correspond to imaginary primary lights X, Y, and Z ( CIE XYZ color space ). All colors can be matched by finding the amounts [X] , [Y] , and [Z] analogously to [R] , [G] , and [B] as defined in Eq. 1 . The functions x ¯ ( λ ) {\displaystyle {\overline {x}}(\lambda )} , y ¯ ( λ ) {\displaystyle {\overline {y}}(\lambda )} , and z ¯ ( λ ) {\displaystyle {\overline {z}}(\lambda )} based on

8094-496: The formula of his colour. In 1828, another scientist, Christian Gmelin then a professor of chemistry in Tübingen, found the process and published his formula. This was the beginning of new industry to manufacture artificial ultramarine, which eventually almost completely replaced the natural product. In 1878 German chemists synthesized indigo . This product rapidly replaced natural indigo, wiping out vast farms growing indigo. It

8208-453: The genus Nessaea , where blue is created by pterobilin . Other blue pigments of animal origin include phorcabilin, used by other butterflies in Graphium and Papilio (specifically P. phorcas and P. weiskei ), and sarpedobilin, which is used by Graphium sarpedon . Blue-pigmented organelles , known as "cyanosomes", exist in the chromatophores of at least two fish species,

8322-533: The green primary of Adobe RGB is more saturated than the equivalent in sRGB, and therefore yields a larger gamut . Otherwise, choice of color space is largely arbitrary and depends on the utility to a specific application. Color space primaries are derived from canonical colorimetric experiments that represent a standardized model of an observer (i.e., a set of color matching functions ) adopted by Commission Internationale de l'Eclairage (CIE) standards. The abbreviated account of color space primaries in this section

8436-424: The hue between blue and violet, as one of the separate colours, though today it is usually considered a hue of blue. In painting and traditional colour theory , blue is one of the three primary colours of pigments (red, yellow, blue), which can be mixed to form a wide gamut of colours. Red and blue mixed together form violet, blue and yellow together form green. Mixing all three primary colours together produces

8550-417: The illumination while letting others pass through, resulting in a colored appearance. The resultant spectral power distribution is predicted by the wavelength-by-wavelength product of the spectral reflectance of the illumination and the product of the spectral reflectances of all of the layers. Overlapping layers of ink in printing mix subtractively over reflecting white paper, while the reflected light mixes in

8664-445: The last main category of colour accepted in a language – adding the colour blue, probably when blue pigments could be manufactured reliably in the culture using that language. The term blue generally describes colours perceived by humans observing light with a dominant wavelength between approximately 450 and 495 nanometres. Blues with a higher frequency and thus a shorter wavelength gradually look more violet, while those with

8778-632: The light from the red glass, filled the church with a bluish violet light. The church became the marvel of the Christian world , and the colour became known as the "bleu de Saint-Denis" . In the years that followed even more elegant blue stained glass windows were installed in other churches, including at Chartres Cathedral and Sainte-Chapelle in Paris. In the 12th century the Roman Catholic Church dictated that painters in Italy (and

8892-516: The light interferes destructively. Diverse colours therefore appear despite the absence of colourants. Egyptian blue , the first artificial pigment, was produced in the third millennium BC in Ancient Egypt. It is produced by heating pulverized sand, copper, and natron . It was used in tomb paintings and funereal objects to protect the dead in their afterlife. Prior to the 1700s, blue colourants for artwork were mainly based on lapis lazuli and

9006-456: The manufacture of wallpaper, and in the 19th century was widely used by French impressionist painters. Beginning in the 1820s, Prussian blue was imported into Japan through the port of Nagasaki . It was called bero-ai , or Berlin blue, and it became popular because it did not fade like traditional Japanese blue pigment, ai-gami , made from the dayflower . Prussian blue was used by both Hokusai , in his wave paintings, and Hiroshige . In 1799

9120-417: The more blue it often appears to the eye. For example, mountains in the distance often appear blue. This is the effect of atmospheric perspective ; the farther an object is away from the viewer, the less contrast there is between the object and its background colour, which is usually blue. In a painting where different parts of the composition are blue, green and red, the blue will appear to be more distant, and

9234-745: The most enduring; blavus , from the Germanic word blau , which eventually became bleu or blue; and azureus , from the Arabic word lazaward , which became azure. Blue was widely used in the decoration of churches in the Byzantine Empire. By contrast, in the Islamic world, blue was of secondary to green, believed to be the favourite colour of the Prophet Mohammed . At certain times in Moorish Spain and other parts of

9348-427: The observer goes, the darker the blue becomes. In the open sea, only about 1% of light penetrates to a depth of 200 metres (see underwater and euphotic depth ). The colour of the sea is also affected by the colour of the sky, reflected by particles in the water; and by algae and plant life in the water, which can make it look green; or by sediment, which can make it look brown. The farther away an object is,

9462-407: The original standard. Currently, ITU-R BT.709-5 primaries are typical for high-definition television . The subtractive color mixing model predicts the resultant spectral power distribution of light filtered through overlaid partially absorbing materials, usually in the context of an underlying reflective surface such as white paper. Each layer partially absorbs some wavelengths of light from

9576-554: The perception of color in terms of the three types of retinal photoreceptors. John Gage 's The Fortunes Of Apelles provides a summary of the history of primary colors as pigments in painting and describes the evolution of the idea as complex. Gage begins by describing Pliny the Elder 's account of notable Greek painters who used four primaries. Pliny distinguished the pigments (i.e., substances) from their apparent colors: white from Milos ( ex albis ), red from Sinope ( ex rubris ), Attic yellow ( sil ) and atramentum ( ex nigris ). Sil

9690-414: The physics of light and perception of color. Art education materials commonly use red, yellow, and blue as primary colors, sometimes suggesting that they can mix all colors. No set of real colorants or lights can mix all possible colors, however. In other domains, the three primary colors are typically red, green and blue, which are more closely aligned to the sensitivities of the photoreceptor pigments in

9804-502: The plant kingdom". In the few plants that exploit structural colouration, brilliant colours are produced by structures within cells. The most brilliant blue colouration known in any living tissue is found in the marble berries of Pollia condensata , where a spiral structure of cellulose fibrils scattering blue light. The fruit of quandong ( Santalum acuminatum ) can appear blue owing to the same effect. Blue-pigmented animals are relatively rare. Examples of which include butterflies of

9918-447: The primaries and that one only needed red, yellow, blue, and green to paint "the whole creation". Red, yellow, and blue as primaries became a popular notion in the 18th and 19th centuries. Jacob Christoph Le Blon , an engraver, was the first to use separate plates for each color in mezzotint printmaking : yellow, red, and blue, plus black to add shades and contrast. Le Blon used primitive in 1725 to describe red, yellow, and blue in

10032-482: The primary colors were white, black, red, and green. In Classical Greece , Empedocles identified white, black, red, and, (depending on the interpretation) either yellow or green as primary colors. Aristotle described a notion in which white and black could be mixed in different ratios to yield chromatic colors; this idea had considerable influence in Western thinking about color. François d'Aguilon 's notion of

10146-404: The primary lights could be adjusted by the participant observer until the matching stimulus matched the test stimulus, as predicted by Grassman's laws of additive mixing. Different standard observers from other color matching experiments have been derived since 1931. The variations in experiments include choices of primary lights, field of view, number of participants etc. but the presentation below

10260-408: The printing industry. Color theorists since the seventeenth century, and many artists and designers since that time, have taken red, yellow, and blue to be the primary colors (see history below). This RYB system, in "traditional color theory", is often used to order and compare colors, and sometimes proposed as a system of mixing pigments to get a wide range of, or "all", colors. O'Connor describes

10374-450: The process colors (and names) cyan and magenta (this is not to say that RYB is the same as CMY, or that it is exactly subtractive, but that there is a range of ways to conceptualize traditional RYB as a subtractive system in the framework of modern color science). Faber-Castell identifies the following three colors: "Cadmium yellow" (number 107) for yellow, "Phthalo blue" (number 110) for blue and "Deep scarlet red" (number 219) for red, as

10488-430: The red closer to the viewer. The cooler a colour is, the more distant it seems. Blue light is scattered more than other wavelengths by the gases in the atmosphere , hence our "blue planet". Some of the most desirable gems are blue, including sapphire and tanzanite . Compounds of copper(II) are characteristically blue and so are many copper-containing minerals. Azurite ( Cu 3 (CO 3 ) 2 (OH) 2 ) , with

10602-414: The red, yellow, and blue color wheel are more aesthetically pleasing, and that good design is about aesthetics. Of course, the notion that all colors can be mixed from RYB primaries is not true, just as it is not true in any system of real primaries. For example, if the blue pigment is a deep Prussian blue , then a muddy desaturated green may be the best that can be had by mixing with yellow. To achieve

10716-599: The reds and the blues so no one colour dominated the picture. Ultramarine was the most prestigious blue of the Renaissance, being more expensive than gold. Wealthy art patrons commissioned works with the most expensive blues possible. In 1616 Richard Sackville commissioned a portrait of himself by Isaac Oliver with three different blues, including ultramarine pigment for his stockings. Primary colours A set of primary colors or primary colours (see spelling differences ) consists of colorants or colored lights that can be mixed in varying amounts to produce

10830-423: The related mineral ultramarine. A breakthrough occurred in 1709 when German druggist and pigment maker Johann Jacob Diesbach discovered Prussian blue . The new blue arose from experiments involving heating dried blood with iron sulphides and was initially called Berliner Blau. By 1710 it was being used by the French painter Antoine Watteau , and later his successor Nicolas Lancret . It became immensely popular for

10944-472: The relative intensities of red, green, and blue light to match each wavelength ( λ {\displaystyle \lambda } ). These functions imply that [ C ] {\displaystyle [C]} units of the test stimulus with any spectral power distribution, P ( λ ) {\displaystyle P(\lambda )} , can be matched by [R] , [G] , and [B] units of each primary where: Each integral term in

11058-404: The response curves for the three types of color photoreceptors found in the human retina: long-wavelength (L), medium-wavelength (M), and short-wavelength (S) cones . The three cone fundamentals are related to the original color matching functions by the following linear transformation (specific to a 10° field): LMS color space comprises three primary lights (L, M, and S) that stimulate only

11172-524: The rest of Europe consequently) to paint the Virgin Mary with blue, which became associated with holiness, humility and virtue. In medieval paintings, blue was used to attract the attention of the viewer to the Virgin Mary. Paintings of the mythical King Arthur began to show him dressed in blue. The coat of arms of the kings of France became an azure or light blue shield, sprinkled with golden fleur-de-lis or lilies. Blue had come from obscurity to become

11286-682: The role of RYB primaries in traditional color theory: A cornerstone component of traditional color theory, the RYB conceptual color model underpins the notion that the creation of an exhaustive gamut of color nuances occurs via intermixture of red, yellow, and blue pigments, especially when applied in conjunction with white and black pigment color. In the literature relating to traditional color theory and RYB color, red, yellow, and blue are often referred to as primary colors and represent exemplar hues rather than specific hues that are more pure, unique, or proprietary variants of these hues. Traditional color theory

11400-400: The royal colour. Blue came into wider use beginning in the Renaissance, when artists began to paint the world with perspective, depth, shadows, and light from a single source. In Renaissance paintings, artists tried to create harmonies between blue and red, lightening the blue with lead white paint and adding shadows and highlights. Raphael was a master of this technique, carefully balancing

11514-414: The same area of the retina is additive , i.e., predicted via summing the spectral power distributions (the intensity of each wavelength) of the individual light sources assuming a color matching context. For example, a purple spotlight on a dark background could be matched with coincident blue and red spotlights that are both dimmer than the purple spotlight. If the intensity of the purple spotlight

11628-460: The silica prior to firing. The cobalt occupies sites otherwise filled with silicon. Methyl blue is the dominant blue pigment in inks used in pens. Blueprinting involves the production of Prussian blue in situ. Certain metal ions characteristically form blue solutions or blue salts. Of some practical importance, cobalt is used to make the deep blue glazes and glasses. It substitutes for silicon or aluminum ions in these materials. Cobalt

11742-542: The size of the gamut of the color space, but the entire human perceptual gamut can be reproduced with just three primaries (albeit imaginary ones as in the CIE XYZ color space ). Some humans (and most mammals ) are dichromats , corresponding to specific forms of color blindness in which color vision is mediated by only two of the types of color receptors. Dichromats require only two primaries to reproduce their entire gamut and their participation in color matching experiments

11856-436: The specifications that they should be nonnegative for all wavelengths, y ¯ ( λ ) {\displaystyle {\overline {y}}(\lambda )} be equal to photometric luminance , and that [ X ] = [ Y ] = [ Z ] {\displaystyle [X]=[Y]=[Z]} for an equienergy (i.e., a uniform spectral power distribution) test stimulus. Derivations use

11970-510: The web, Jason Beaird writes: The reason many digital artists still keep a red, yellow, and blue color wheel handy is because the color schemes and concepts of traditional color theory are based on that model. ... Even though I design mostly for the Web—a medium that's displayed in RGB—I still use red, yellow, and blue as the basis for my color selection. I believe that color combinations created using

12084-560: Was announced after the occupation of Kotlin Island in 1703. Since then, the flag with St. Andrew's cross has been used as a symbol of Russia's access to the four seas — the White , Baltic , Azov and Caspian . In 1705 a drawing of a three-striped St. Andrew's flag was placed in a book by Carolus Allard , published in Holland . Since 1709 St. Andrew's cross on a white field was placed in

12198-473: Was doubled it could be matched by doubling the intensities of both the red and blue spotlights that matched the original purple. The principles of additive color mixing are embodied in Grassmann's laws . Additive mixing is sometimes described as "additive color matching" to emphasize the fact the predictions based on additivity only apply assuming the color matching context. Additivity relies on assumptions of

12312-409: Was essential in the determination of cone fundamentals leading to all modern color spaces. Despite most vertebrates being tetrachromatic , and therefore requiring four primaries to reproduce their entire gamut, there is only one scholarly report of a functional human tetrachromat , for which trichromatic color models are insufficient. The perception elicited by multiple light sources co-stimulating

12426-682: Was historically confused as a blue pigment between the 16th and 17th centuries, leading to claims about white, black, red, and blue being the fewest colors required for painting. Thomas Bardwell , an 18th century Norwich portrait painter, was skeptical of the practical relevance of Pliny's account. Robert Boyle , the Irish chemist, introduced the term primary color in English in 1664 and claimed that there were five primary colors (white, black, red, yellow, and blue). The German painter Joachim von Sandrart eventually proposed removing white and black from

12540-707: Was mined in the Sar-i Sang mines, in Shortugai , and in other mines in Badakhshan province in northeast Afghanistan . Lapis lazuli artifacts, dated to 7570 BC, have been found at Bhirrana , which is the oldest site of Indus Valley civilisation . Lapis was highly valued by the Indus Valley Civilisation (7570–1900 BC). Lapis beads have been found at Neolithic burials in Mehrgarh ,

12654-684: Was possibly based on the art of paint mixing. Mixing pigments for the purpose of creating realistic paintings with diverse color gamuts is known to have been practiced at least since Ancient Greece (see history section ). The identity of a/the set of minimal pigments to mix diverse gamuts has long been the subject of speculation by theorists whose claims have changed over time, for example, Pliny's white, black, one or another red, and "sil", which might have been yellow or blue; Robert Boyle's white, black, red, yellow, and blue; and variations with more or fewer "primary" color or pigments. Some writers and artists have found these schemes difficult to reconcile with

12768-417: Was proposed by Ewald Hering in which he described the four unique hues (later called psychological primaries in some contexts): red, green, yellow and blue. To Hering, the unique hues appeared as pure colors, while all others were "psychological mixes" of two of them. Furthermore, these colors were organized in "opponent" pairs, red vs. green and yellow vs. blue so that mixing could occur across pairs (e.g.,

12882-547: Was replaced by the finer indigo from America. In the 19th century, synthetic blue dyes and pigments gradually replaced organic dyes and mineral pigments. Dark blue became a common colour for military uniforms and later, in the late 20th century, for business suits. Because blue has commonly been associated with harmony, it was chosen as the colour of the flags of the United Nations and the European Union . In

12996-467: Was used in ancient Egypt for jewellery and ornament and later, in the Renaissance , to make the pigment ultramarine , the most expensive of all pigments. In the eighth century Chinese artists used cobalt blue to colour fine blue and white porcelain . In the Middle Ages , European artists used it in the windows of cathedrals . Europeans wore clothing coloured with the vegetable dye woad until it

#738261