Primary and Secondary Color Basics
- Primary colors are the colors used to create all other colors.
- Secondary colors are those created by mixing any two of the primary colors.
Color light compared with color pigment
Most people are not aware that the primary colors of light are different than those of pigments (for example, paint). This is because they provide color to us in different ways.
- Pigment is subtractive, meaning that the color we see is actually the color that is not absorbed by the surface.
- This means that when we see sunlight on a red wall, the red that we perceive is the color that the wall does not absorb from the full spectrum of color light.
- White is often painted on objects to reflect all light and thus minimize the accompanying absorption of heat energy because of this principle. Black and dark colors absorb more light and heat.
- Light is additive. This is the color light that we perceive when different amounts of the primary colors of light are mixed together.
- This includes the color we perceive being emitted from a computer monitor or television screen.
- If you were to quickly look through a magnifying glass at such a screen, and I am not recommending you do so, you would see that what appears to be white actually consists of rows and rows of tiny red, green and blue dots of color light in tiny groupings.
- Even more intriguing is that yellow consists of red and green lights. Who would have guessed?
- On the web, all color is specified based on differing values of red, green, and blue.
- Black is no light, and white is the highest amounts of red, green, and blue.
Primary and Secondary Colors of Light (additive color)
- Demonstration using color lights
- En Français! Ajout de coulour. Cette synthèse est formidable!
- This means: In French! Additive color. This example is wonderful!
Primary and Secondary Colors of Pigment (subtractive color)
- This type of color has no bearing on the colors used on the web because web colors are derived from colored light that is emitted by the tiny dots that a computer monitor consists of.
- What we see is the color that is not absorbed by an object - we see the color that remains after absorption.
- This is why it is called subtractive color.
- You probably know about these primary colors from elementary school art classes.
- The illustration depicts the primary colors that I learned red, yellow, and blue.
- Please see the important information following this illustration.
Important note!
- The "actual" primary colors of pigment (subtractive color), based on an evenly spaced color wheel, are, interestingly, also the secondary colors of light!:
- yellow
- cyan
- magenta
- The "actual" secondary colors of pigment (subtractive color) are, again, interestingly, the same as the primary colors of light:
- red
- green
- blue
- These "actual" primary colors of pigments are used in the CMYK color model that is often used in Photoshop and elsewhere. CMYK refers to the three primary colors CMY (cyan, magenta, yellow) and also black (K).
- Those are often the only inks used for most printing.
- The letter K is used to represent black because the black printing plate was historically referred to as the Key (that is, the most important) printing plate.
For more information, read this informative Wikipedia article about the various definitions of primary colors, in particular this section about the primary colors of pigment (subtractive color).