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There are three types of color mixing models, depending on the relative brightness of the resultant mixture: additive, subtractive, and average.^[1] In these models, mixing black and white will yield white, black and gray, respectively. Physical mixing processes, e.g. mixing light beams or oil paints, will follow one or a hybrid of these 3 models.^[1] Each mixing model is associated with several color models, depending on the approximate primary colors used. The most common color models are optimized to human trichromatic color vision, therefore comprising three primary colors.^[1]^: 4.2

Mixing models

Additive model

Additive mixing combines two or more colors into a mixture with brightness equal to the sum of the components' brightnesses.^[1]^: 4.4 An ideal physical model to demonstrate the additive model comprises two superimposed colored lights aimed at the observer. The additive model is usually demonstrated by reflecting two beams of colored light off a white, matte surface (e.g. projectors) or by analyzing the sub-pixels of a color display, both of which follow the additive model closely.

The most common additive color model is the RGB color model, which uses three primary colors: red, green, and blue. This model is the basis of most color displays. Some modern displays are Multi-primary color displays, which have 4-6 primaries (RGB, plus cyan, yellow and/or magenta) in order to increase the size of the color gamut. For all additive color models, the absence of all primaries results in black. For practical additive color models, an equal superposition of all primaries results in neutral (gray or white). In the RGB model, an equal mixture of red and green is yellow, an equal mixture of green and blue is cyan and an equal mixture of blue and red is magenta.^[1]^: 4.2 Yellow, cyan and magenta are the secondary colors of the RGB model.

Subtractive model

Subtractive mixing combines two or more colors into a mixture with brightness lower than either of the two components' brightnesses. An ideal physical model to demonstrate the subtractive model comprises a white light transmitting through two colored filters, each of which subtract a portion of the white light, transmitting a light of the combined color.^[1]^: 5.2 However, the subtractive model is usually demonstrated with dyes or pigments, such as paint or ink, which often do not closely follow the subtractive model. How well they follow the model depends mostly on the opacity of the pigment or dye.^[1]^: 6.1

The most common subtractive color models are the CMYK color model, CMY color model and RYB color model.^[1]^: 6.2 The CMYK model used in color printing uses cyan, magenta, yellow, and black primaries. For all subtractive color models, the absence of all color primaries results in white. For ideal subtractive color models, an equal superposition of all primaries results in a neutral (dark gray or black). The CMYK model adds a black primary to improve the darkness of blacks, where the CMY model can only mix to dark gray or only achieves black inefficiently, i.e. by using lots of the primary pigments. In the CMY model, an equal mixture of cyan and magenta is blue, an equal mixture of magenta and yellow is red and an equal mixture of yellow and cyan is green. These mixtures are the secondary colors of the CMY model, which are the same as the primaries of the additive RGB model and vice versa.

Average model

Average mixing (sometimes additive-average) combines two colors into a mixture with brightness equal to the average of the two components' brightnesses.^[1]^: 4.4 This model is often demonstrated with a Newton disc, where a wheel comprising several color wedges along the circumference is rotated at high speed, such that the human eye cannot temporally differentiate the colors, and they combine to a color with the average brightness (weighted to the angle each color takes up). Another physical model mimics pointillism or halftone printing, where the spatial acuity of the human eye is not sufficient to spatially differentiate the colors, and they combine to a mixture with the average brightness.^[1]^: 4.4 There are no common color models that explicitly use the average model, though many additive or subtractive models can be described in part by the average model.

Pigment mixing

In the practical mixing of pigments, the subtractive model is usually not closely followed. How the pigment mixing behaves depends strongly on the opacity of the pigments.^[1]^: 6.1 Ideally transparent pigments transmit and absorb light, but do not reflect or scatter it and mix according to the subtractive model. Ideally opaque pigments reflect or absorb light, but do not transmit it and mix according to the average model. Most real paints reflect, transmit and scatter light, so mix according to a hybrid between the subtractive and average models.^[1]^: 6.1 Paint color mixer is also affected by the media used as wetting, deagglomeration, and dispersing agents for the pigments. These agents all have their own transparency/opacity and color properties and can also alter the transparency and color of pigments.^{[citation needed]}

For example, mixing red and yellow can result in a shade of orange, generally with a lower chroma or reduced saturation than at least one of the component colors. In some combinations, a mix of blue and yellow paint produces green. This occurs when there is sufficient transparency in the pigments, allowing light to penetrate into the mixed paint, where the two colors together absorb light except wavelengths in the green range. Alternately, if the pigments are highly opaque, a combination of blue and yellow paint appears more grayish. In this case, pigment particles simply reflect whatever light hits the outer paint surface, where both blue and yellow light gets reflected and averaged together.

Halftone printing uses non-opaque inks, such that the light transmits once through the ink, reflects off the white substrate (e.g. paper) and transmits a second time through the ink. Increasing the ink printed on the page decreases the brightness of light, and halftone printing follows the subtractive model well.

References

^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l Briggs, David. "The Dimensions of Colour". Retrieved 2 January 2024.

[BRIGGS-1] ^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l Briggs, David. "The Dimensions of Colour". Retrieved 2 January 2024.

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 {{Short description|Producing colors by combining the primary or secondary colors in different amounts}}
+There are three types of '''color mixing''' models, depending on the relative brightness of the resultant mixture: ''additive'', ''subtractive'', and ''average''.<ref name="BRIGGS">{{cite web |last1=Briggs |first1=David |title=The Dimensions of Colour |url=http://www.huevaluechroma.com/ |access-date=2 January 2024}}</ref> In these models, mixing black and white will yield white, black and gray, respectively. Physical mixing processes, e.g. mixing light beams or [[oil paint]]s, will follow one or a hybrid of these 3 models.<ref name="BRIGGS"/> Each mixing model is associated with several [[color models]], depending on the approximate [[primary colors]] used. The most common color models are optimized to human [[trichromacy|trichromatic color vision]], therefore comprising three primary colors.{{r|BRIGGS|p=4.2}}
-[[File: Additive color mixing.jpg|thumb|Additive color mixing can be illustrated with colored lights.]]
+==Mixing models==
-There are three types of '''color mixing''': ''additive'', ''subtractive'', and ''average''. In first two cases, mixing is typically described in terms of three [[Primary color|primary colors]] and three [[secondary colors]] (colors made by mixing two of the three primary colors in equal amounts). Subtractive mixing with all three primaries will result in [[black]], while additive mixing with all three primaries will result in [[white]].
+===Additive model===
-==Additive mixing==
 {{Main|Additive color}}
-[[File: Additive color mixing simulated.png|thumb|A simulated example of additive color mixing. Additive primaries act as sources of light.  The primaries red, green, and blue combine pairwise to produce the additive secondaries cyan, magenta, and yellow. Combining all three primaries (center) produces white.]]
+[[File: Additive color mixing simulated.png|thumb|A simulated example of additive color mixing in the RGB model. The primaries red, green, and blue combine pairwise to produce the additive secondaries cyan, magenta, and yellow. Combining all three primaries (center) produces white.]]
+Additive mixing combines two or more colors into a mixture with brightness equal to the ''sum'' of the components' brightnesses.{{r|BRIGGS|p=4.4}} An ideal physical model to demonstrate the additive model comprises two superimposed colored lights aimed at the observer. The additive model is usually demonstrated by reflecting two beams of colored light off a white, matte surface (e.g. [[projector]]s) or by analyzing the sub-pixels of a [[Visual display unit|color display]], both of which follow the additive model closely.
-The additive mixing of colors is not commonly taught to children, as it does not correspond to the mixing of physical substances (such as paint) which would correspond to subtractive mixing.  Two beams of light that are superimposed mix their colors additively.
-By convention, the three primary colors in additive mixing are [[red]], [[green]], and [[blue]]. In the absence of light of any color, the result is black. If all three primary colors of light are mixed in equal proportions, the result is neutral (gray or white). When the red and green lights mix, the result is [[yellow]]. When green and blue lights mix, the result is [[cyan]]. When the blue and red lights mix, the result is [[magenta]].
+The most common additive color model is the [[RGB color model]], which uses three primary colors: [[red]], [[green]], and [[blue]]. This model is the basis of most color displays. Some modern displays  are [[Multi-primary color display]]s, which have 4-6 primaries (RGB, plus cyan, yellow and/or magenta) in order to increase the size of the [[color gamut]]. For all additive color models, the absence of all primaries results in black. For practical additive color models, an equal superposition of all primaries results in neutral (gray or white). In the RGB model, an equal mixture of red and green is [[yellow]], an equal mixture of green and blue is [[cyan]] and an equal mixture of blue and red is [[magenta]].{{r|BRIGGS|p=4.2}} Yellow, cyan and magenta are the secondary colors of the RGB model.
+===Subtractive model===
-Red-green–blue additive mixing is used in television and computer [[Visual display unit|monitors]], including smartphone displays, to produce a wide range of colors. A screen [[pixel]] uses a juxtaposition of these three primary colors. Projection televisions sometimes have three projectors, one for each primary color. these coloring in techniques should be used by children earlier on in there life
+{{Main|Subtractive color}}
+[[File:CMY ideal version.svg|thumb|right|A simulated example of (idealized) subtractive color mixing in the CMY model. The primaries cyan, magenta and yellow combine pairwise to produce subtractive secondaries red, green, and blue. Combining all three primaries (center) absorbs all light and produces black. In practical CMY color models, the center is usually dark gray and a separate black pigment is required to produce black (CMYK model).]]
+Subtractive mixing combines two or more colors into a mixture with brightness ''lower'' than either of the two components' brightnesses. An ideal physical model to demonstrate the subtractive model comprises a white light transmitting through two colored filters, each of which subtract a portion of the white light, [[Transmittance|transmitting]] a light of the combined color.{{r|BRIGGS|p=5.2}} However, the subtractive model is usually demonstrated with [[dye]]s or [[pigment]]s, such as [[paint]] or [[ink]], which often do not closely follow the subtractive model. How well they follow the model depends mostly on the [[opacity]] of the pigment or dye.{{r|BRIGGS|p=6.1}}
-Colors are colors as i shade this colors and the colors shade with the colors of the colors and the colors
+The most common subtractive color models are the [[CMYK color model]], [[CMY color model]] and [[RYB color model]].{{r|BRIGGS|p=6.2}} The CMYK model used in color printing uses [[cyan]], [[magenta]], [[yellow]], and black primaries. For all subtractive color models, the absence of all color primaries results in white. For ideal subtractive color models, an equal superposition of all primaries results in a neutral (dark gray or black). The CMYK model adds a black primary to improve the darkness of blacks, where the CMY model can only mix to dark gray or only achieves black inefficiently, i.e. by using lots of the primary pigments. In the CMY model, an equal mixture of cyan and magenta is [[blue]], an equal mixture of magenta and yellow is [[red]] and an equal mixture of yellow and cyan is [[green]]. These mixtures are the secondary colors of the CMY model, which are the same as the primaries of the additive RGB model and vice versa.
-==Subtractive mixing==
-{{Main|Subtractive color}}
-[[File:SubtractiveColorMixing.png|thumb|right|A simulated example of (idealized) subtractive color mixing.  An external source of illumination is assumed, and each primary attenuates (absorbs) some of that light.  The standard subtractive primaries cyan, magenta, and yellow combine pairwise to make subtractive secondaries red, green, and blue (which  are additive primaries, or in practice somewhat darker and less-saturated versions of typical additive primaries).  Combining all three primaries (center) absorbs all the light, resulting in black. For real pigments, the results would be somewhat complicated by opacity and mixing behavior, and in practice adding a fourth pigment such as black may be helpful.]]
+===Average model===
-The mixing of colored physical substances corresponds to subtractive color mixing, hence it corresponds to our intuition about mixing colors. To explain the mechanism, consider paint. Red paint is red because, when the ambient light strikes it, the composition of the material is such that it absorbs all other colors in the visible spectrum except for red. The red light, not being absorbed, is reflected by the paint and seen by our eyes. This same mechanism describes the color of material objects – note that light is not a material object – and so applies to the yellow paint as well. Making recourse to the figure above demonstrating additive color mixing, one sees that yellow light is composed of an (additive) mixture of red and green light. When we mix the two paints, the resulting substance has red paint and yellow paint. The yellow paint absorbs all colors except for red and green. However, the red paint will absorb the green reflected by the yellow paint. The red paint can be said to subtract the green from the yellow paint. The resulting paint reflects only red light and so appears red to our eyes. Note however that this description is theoretical and that the mixing of [[pigment]]s does not correspond to ideal subtractive color mixing because some light from the subtracted color is still being reflected by one component of the original paint. This results in a darker and desaturated color compared to the color that would be achieved with ideal filters.
+Average mixing (sometimes additive-average) combines two colors into a mixture with brightness equal to the ''average'' of the two components' brightnesses.{{r|BRIGGS|p=4.4}} This model is often demonstrated with a [[Newton disc]], where a wheel comprising several color wedges along the circumference is rotated at high speed, such that the human eye cannot temporally differentiate the colors, and they combine to a color with the average brightness (weighted to the angle each color takes up). Another physical model mimics [[pointillism]] or [[halftone|halftone printing]], where the spatial acuity of the human eye is not sufficient to spatially differentiate the colors, and they combine to a mixture with the average brightness.{{r|BRIGGS|p=4.4}} There are no common color models that explicitly use the average model, though many additive or subtractive models can be described in part by the average model.
+==Pigment mixing==
-The three [[primary colors]] typically used in subtractive color mixing systems are [[cyan]], [[magenta]], and [[yellow]], corresponding to the [[CMY color model]] and [[CMYK color model]] widely used in color printing. In subtractive mixing of color, the absence of color is white and the presence of all three primary colors makes a neutral dark gray or black. The secondary colors are the same as the primary colors from additive mixing and vice versa.  Subtractive mixing is used to create a variety of colors when [[printing]] or painting on paper or other white substrates, by combining a small number of [[ink]] or paint colors. Red is created by mixing magenta and yellow (removing green and blue). Green is created by mixing cyan and yellow (removing red and blue respectively). Blue is created by mixing cyan and magenta (removing red and green). Black can be approximated by mixing cyan, magenta, and yellow, although real pigments are not ideal and so pure black is nearly impossible to achieve.
+In the practical mixing of pigments, the subtractive model is usually not closely followed. How the pigment mixing behaves depends strongly on the [[opacity]] of the pigments.{{r|BRIGGS|p=6.1}} Ideally transparent pigments transmit and absorb light, but do not reflect or scatter it and mix according to the subtractive model. Ideally opaque pigments reflect or absorb light, but do not transmit it and mix according to the average model. Most real paints reflect, transmit and scatter light, so mix according to a hybrid between the subtractive and average models.{{r|BRIGGS|p=6.1}} Paint [https://imagetocolor.com/mix-colors-online color mixer] is also affected by the media used as wetting, deagglomeration, and dispersing agents for the pigments. These agents all have their own transparency/opacity and color properties and can also alter the transparency and color of pigments.{{cn|date=January 2024}}
+[[File:Red and yellow paint palette.jpg|thumb|Red and yellow paints being mixed on a palette]]
-==Average mixing==
+For example, mixing red and yellow can result in a shade of orange, generally with a lower chroma or reduced saturation than at least one of the component colors. In some combinations, a mix of blue and yellow paint produces green. This occurs when there is sufficient transparency in the pigments, allowing light to penetrate into the mixed paint, where the two colors together absorb light except wavelengths in the green range. Alternately, if the pigments are highly opaque, a combination of blue and yellow paint appears more grayish. In this case, pigment particles simply reflect whatever light hits the outer paint surface, where both blue and yellow light gets reflected and averaged together.
-Average mixing obtains a new color out of two component colors, with brightness equal to the average of the two components. This is different from additive mixing, which results in a color lighter than the colors being mixed; and from subtractive mixing, which results in a color darker than the colors being mixed. Some examples of average mixing are: black and white averages to gray, and blue and red averages to purple. Average mixing has eight primary colors: [[white]], [[cyan]], [[magenta]], [[yellow]], [[red]], [[green]], [[blue]], and [[black]].
+[[Halftone]] printing uses non-opaque inks, such that the light transmits once through the ink, reflects off the white substrate (e.g. paper) and transmits a second time through the ink. Increasing the ink printed on the page decreases the brightness of light, and halftone printing follows the subtractive model well.
-Another example of average mixing is different colors on a disk, which results in an average color when the disk spins fast enough.
-Average mixing can be confused with subtractive mixing. For example, even though red and blue averages to purple, an attempt to make a particular shade of purple by mixing red and blue paint may fail, since there is no purple spectrum between the red and blue spectra.<ref>{{cite web |url= https://science.nasa.gov/ems/09_visiblelight |title= Visible Light }}</ref>
 ==See also==
+*[[Additive color]]
+*[[Color theory]]
 *[[Impossible color]]s
-*[[Mixed Blend ]]
+*[[Subtractive color]]
-*[[Color theory]]
 ==References==
-*[[David Macaulay|Macaulay, David]] and Neil Ardley (1988). ''The New Way Things Work''. London: Dorling Kindersley Ltd. {{ISBN|0-395-93847-3}}.
 {{Reflist}}