There are two main types of color mixing: additive color mixing and subtractive color mixing. Additive color mixing is creating a new color by a process that adds one set of wavelengths to another set of wavelengths. Additive color mixing is what happens when lights of different wavelengths are mixed. When we add all of the different wavelengths of sunlight, we see white light rather than many individual colors. It is called additive because all of the wavelengths still reach our eyes. It is the combination of different wavelengths that creates the diversity of colors. Subtractive color mixing is creating a new color by the removal of wavelengths from a light with a broad spectrum of wavelengths. Subtractive color mixing occurs when we mix paints, dyes, or pigments. When we mix paints, both paints still absorb all of the wavelengths they did previously, so what we are left with is only the wavelengths that both paints reflect. It is called subtractive mixing because when the paints mix, wavelengths are deleted from what we see because each paint will absorb some wavelengths that the other paint reflects, thus leaving us with a lesser number of wavelengths remaining afterward. So the easy way to remember the difference between additive and subtractive color mixing is that additive color mixing is what happens when we mix lights of different colors whereas subtractive color mixing occurs when we mix paints or other colored material.
Use this activity to explore color mixing and its various properties.
To see the illustration in full screen, which is recommended, press the Full Screen button, which appears at the top of the page.
Below is a list of the ways that you can alter the illustration. The settings include the following:
Screen Area: click on one of the primaries to move it around. Mixing only
occurs where primary circles overlap.
Type: choose whether to explore additive or subtractive color mixing.
Primaries: Control the intensity of each of the primaries: Red, Green and Blue for additive, and Cyan, Magenta and Yellow for Subtractive.
Background: If you are doing subtractive color mixing, the you can only subtract wavelengths that are present. In this illustration, this is shown by the background color. Change the background color and see how that alters the colors you can create with subtractive color mixing.
Reset Positions: return the the primary circles to their original position.
Pressing this button restores the settings to their default values.