Why do printers have CMYK ink instead of RYB & black ink?
In: 2442
RGB are the “additive” colors which can recreate all the colors the human eye can see when added to black.
Pigment works by “subtracting” colors from white. You cannot “add” color to white paper as it already reflects all color. Instead you remove colors by applying color-absorbing pigment. Cyan absorbs the color red, yellow absorbs blue, and magenta absorbs green.
This means that to create “green” you have to add all the colors that are not magenta (cyan and yellow). If you instead used green pigment, you would be able to make green with only a single pigment but you would lose the ability to create cyan or yellow (or else the cyan and yellow would be too dark and murky).
Now pigments don’t behave exactly the way we want them to, and they tend to create “layers” and interact with each other. This is why some printers do add extra colors. Black is an example, as it cannot easily be made by mixing all pigments. This tends to produce brown instead, probably due to the fact that the pigments form layers and are somewhat reflective. Ideally only the white paper back would be reflective and the pigments only absorptive.
Now why are red, green, and blue primary colors? Because they correspond to the [3 wavelengths of light that the cones in your retina are sensitive to.](https://i.stack.imgur.com/JtqUU.png) Also many people seem to be unfamiliar with what the color [“true” green](https://www.solidbackgrounds.com/images/1920×1080/1920×1080-bright-green-solid-color-background.jpg) looks like (Among us players call it “lime”). It appears the brightest out of all 3 primary colors simply because that is how the brain perceives it (but it isn’t any brighter in actuality than red or blue). Humans tend to associate the color green with forests and leaves, but this color is usually a desaturated and darker green.
Cyan, magenta, and yellow are the primary colors of pigment, subtractive color.
Red, green, and blue are the primary colors of light, additive color.
Red, yellow, and blue aren’t actually a set of primary colors, that’s a lie we are told in elementary school. That color theory is really just an approximation of cyan, magenta, and yellow.
If you mix red and green light, you get yellow.
If you mix green and blue light, you get cyan.
If you mix blue and red light, you get magenta.
All 3 make white.
You can mix varying amounts of each color to make any color with light.
If you mix cyan and magenta pigment, the cyan absorbs red, and the magenta absorbs green, so you get something that only reflects blue, so you get blue.
If you mix yellow and magenta pigment, the yellow absorbs blue, and the magenta absorbs green, so you get something that only reflects red, so you get red.
If you mix cyan and yellow pigment, the cyan absorbs red, and the yellow absorbs blue, so you get something that only reflects green, so you get green.
If you mix all 3, you would get black if they were perfect pigments, but it ends up as more of a gray color. We use a black pigment to substitute it as well as to darken other colors.
Edit: greeb
Cyan, magenta, and yellow are the primary colors of pigment, subtractive color.
Red, green, and blue are the primary colors of light, additive color.
Red, yellow, and blue aren’t actually a set of primary colors, that’s a lie we are told in elementary school. That color theory is really just an approximation of cyan, magenta, and yellow.
If you mix red and green light, you get yellow.
If you mix green and blue light, you get cyan.
If you mix blue and red light, you get magenta.
All 3 make white.
You can mix varying amounts of each color to make any color with light.
If you mix cyan and magenta pigment, the cyan absorbs red, and the magenta absorbs green, so you get something that only reflects blue, so you get blue.
If you mix yellow and magenta pigment, the yellow absorbs blue, and the magenta absorbs green, so you get something that only reflects red, so you get red.
If you mix cyan and yellow pigment, the cyan absorbs red, and the yellow absorbs blue, so you get something that only reflects green, so you get green.
If you mix all 3, you would get black if they were perfect pigments, but it ends up as more of a gray color. We use a black pigment to substitute it as well as to darken other colors.
Edit: greeb
[Here is a color wheel showing many pigments used in painting and printing.](https://painterfactory.com/cfs-file/__key/communityserver-discussions-components-files/19/cwheel06sfsfsfsfs.png) Roughly speaking, if you draw a shape using your chosen pigments, you will be able to make all the colors in that shape, but not out of that shape.
If you draw a triangle around benzimida yellow, quinacridone megenta and pthalo cyan, you will see that your greens, oranges and violets will not be very saturated.
Any three hues is a big compromise, but RBY is an unusually bad choice, because Red and Yellow are close to each other, leaving only B to cover everything from violets to magentas to greens.
In reality, even three ‘normal’ pigments like ultramarine, cadmium red and hansa yellow will be able to reproduce 99% of the colors you see. Very saturated colors are not common. A big reason why people teach color mixing with RBY is that it is easy to control the value of a mixture using yellow and blue since yellow is intrinsically light and blue is intrinsically dark. Good artists can rapidly mix almost any non-saturated color in their environment using these colors.
If you want the biggest color ‘space’ also called a ‘gamut’ you need to choose as many pigments from the periphery of this graph as possible.
Note also that there are not a ton of good options for very saturated green yellows and violets. I am not sure why this is the case, but these colors will potentially be more saturated coming from an emmissive source.
Cyan, magenta, and yellow are the primary colors of pigment, subtractive color.
Red, green, and blue are the primary colors of light, additive color.
Red, yellow, and blue aren’t actually a set of primary colors, that’s a lie we are told in elementary school. That color theory is really just an approximation of cyan, magenta, and yellow.
If you mix red and green light, you get yellow.
If you mix green and blue light, you get cyan.
If you mix blue and red light, you get magenta.
All 3 make white.
You can mix varying amounts of each color to make any color with light.
If you mix cyan and magenta pigment, the cyan absorbs red, and the magenta absorbs green, so you get something that only reflects blue, so you get blue.
If you mix yellow and magenta pigment, the yellow absorbs blue, and the magenta absorbs green, so you get something that only reflects red, so you get red.
If you mix cyan and yellow pigment, the cyan absorbs red, and the yellow absorbs blue, so you get something that only reflects green, so you get green.
If you mix all 3, you would get black if they were perfect pigments, but it ends up as more of a gray color. We use a black pigment to substitute it as well as to darken other colors.
Edit: greeb
The red in your childhood paint has yellow in it. Red is not a primary color. You were lied to.
Cyan
Magenta
Yellow
blacK
These are the primary colors of applied art. Sometimes whites are used but that requires paint or a specific type of printer for anything offset. Substrate will affect color purity.
Red
Green
Blue
These are the primary colors of light. Red and green make yellow. All three make white. Their absence is black.
I work in art and product design. I’ve worked in print. I’ve been a computer user for 40 years.
Color is perception to an extent of course. The light will affect tone. Cool. Warm. Etc.
There’s other models. HSB (Hue Saturation Brightness) and proprietary shît like Pantone. Metallics use flake or fun glazes.
Paints historically have used pure pigments now chemical is cheaper. Traditional red hues use literal gold for instance.
Anyhow. It’s a whole world.
The red in your childhood paint has yellow in it. Red is not a primary color. You were lied to.
Cyan
Magenta
Yellow
blacK
These are the primary colors of applied art. Sometimes whites are used but that requires paint or a specific type of printer for anything offset. Substrate will affect color purity.
Red
Green
Blue
These are the primary colors of light. Red and green make yellow. All three make white. Their absence is black.
I work in art and product design. I’ve worked in print. I’ve been a computer user for 40 years.
Color is perception to an extent of course. The light will affect tone. Cool. Warm. Etc.
There’s other models. HSB (Hue Saturation Brightness) and proprietary shît like Pantone. Metallics use flake or fun glazes.
Paints historically have used pure pigments now chemical is cheaper. Traditional red hues use literal gold for instance.
Anyhow. It’s a whole world.
The red in your childhood paint has yellow in it. Red is not a primary color. You were lied to.
Cyan
Magenta
Yellow
blacK
These are the primary colors of applied art. Sometimes whites are used but that requires paint or a specific type of printer for anything offset. Substrate will affect color purity.
Red
Green
Blue
These are the primary colors of light. Red and green make yellow. All three make white. Their absence is black.
I work in art and product design. I’ve worked in print. I’ve been a computer user for 40 years.
Color is perception to an extent of course. The light will affect tone. Cool. Warm. Etc.
There’s other models. HSB (Hue Saturation Brightness) and proprietary shît like Pantone. Metallics use flake or fun glazes.
Paints historically have used pure pigments now chemical is cheaper. Traditional red hues use literal gold for instance.
Anyhow. It’s a whole world.
light mixing creates the colors
with RGB, you’re directly creating the light, so you mix them to get the colors. they call this additive because you add colors together
with CMYK, you filter light that either goes through it, or reflects off of it. so light created by something like an LED will be RGB, and things like light filters or paint, will be CMYK. think of them as the opposite. for cyan, the purple and yellow get absorbed, and only the blue/green comes through, for example
it’s like building a snowman. CMYK is like starting with a giant block of snow. you carve it and remove snow until you’re left with a snowman. it’s subtractive. if you gather snow to build the snowman, that’s how RGB works. in the end, you get the same result, but you got there from opposite directions. hope that makes a little sense. YouTube probably has some cool videos on the topic if you want illustrations
light mixing creates the colors
with RGB, you’re directly creating the light, so you mix them to get the colors. they call this additive because you add colors together
with CMYK, you filter light that either goes through it, or reflects off of it. so light created by something like an LED will be RGB, and things like light filters or paint, will be CMYK. think of them as the opposite. for cyan, the purple and yellow get absorbed, and only the blue/green comes through, for example
it’s like building a snowman. CMYK is like starting with a giant block of snow. you carve it and remove snow until you’re left with a snowman. it’s subtractive. if you gather snow to build the snowman, that’s how RGB works. in the end, you get the same result, but you got there from opposite directions. hope that makes a little sense. YouTube probably has some cool videos on the topic if you want illustrations
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