Additive color combinations happen when light sources of
different wavelengths are added together. This is how colors are
displayed on computer monitors and TVs. Web pages, for example, have
codes that allow the author to specify the amount of different colors
that can be added together. In the following examples, codes are used
to combine different wavelengths of light and produce different colors.
Blue primary: Red=0%, Green=0%, Blue=100% (Hex #0000FF)
Red primary: Red=100%, Green=0%, Blue=0% (Hex #FF0000)
Green primary: Red=0%, Green=100%, Blue=0% (Hex #00FF00)
Let's start mixing!
If we add equal parts of red and green, we get ...
In this case, yellow is Red=100%, Green=100%, and Blue=0% (Hex
Let's add equal parts of red and blue:
The above purple is red=100%, green=0, and blue=100% (Hex #FF00FF).
This is the result if we add equal amounts of blue and green:
The above combination is red=0, green=100%, and blue=100% (Hex #00FFFF)
What happens if we have equal amounts of all three primaries?
This one is red=100%, green=100%, and blue=100% (Hex #FFFFFF). Combining
equal amounts of all three primaries gives us white.
What would the absence of all three primaries look like?
Black is red=0%, green=0%, and blue=0% (Hex #000000). If we have none
of the three primaries, we are left with nothing. This looks black because
there is no light coming from it.
Colors on the web are generally expressed in hexidecimal. The first
two digits of these codes represent red, the second pair represents green,
and the last pair represents blue. 00 is an absence of a particular primary
color, whereas FF is the maximal value for a particular primary. For example,
#FF0000 is red, #00FF00 is green, and #0000FF is blue.