An Introduction toMixing Colors

What happens if you mix colors of paint?

Half of you will mix blue, red, and yellow acrylic paints from Michaels ($1.49 a bottle). Choose two colors to mix to create a new color. Also mix the three colors to create a color

Half of you will mix cyan, magenta, and yellow acrylic paints from a art supply store ($7 to $10 a tube). Choose two colors to mix to create a new color. Also mix the three colors to create a color.

Half of you experimented with mixing blue, red, and yellow paints.

What colors did you produce?

Half of you experimented with mixing cyan, magenta, and yellow paints.

What colors did you produce?

Students are often introduced to a study of color by mixing blue, red, and yellow paints.

Cyan, Magenta, and Yellow are primary color pigments often used in printing.

Primary colors of paints and pigments are called subtractive primary colors.

Red paint absorbs blue and green light. Blue paint absorbs red and green light. Yellow paint absorbs blue and violet. Mixing these three primary colors of paint results in a muddy dark brown color. This means that not all wavelengths of incident light were absorbed.

Cyan absorbs red light. Yellow absorbs blue light. Magenta absorbs green light. A mix of equal amounts of each of these primary colors results in a black color. That means that all wavelengths of incident light were absorbed.

What happens if we mix colors of light?

Red, Green, and Blue are commonly referred to as the primary colors of light

Shining two pure primary colors of light of equal intensity onto a screen produces pure complementary colors.

cyan

magenta

yellow

Red, green, and blue light are called additive primary colors.

Red light has the lowest frequency. Green light has a middle frequency. Blue light has the highest frequency. Light from the different frequency regions combine to form white light.

Three other colors from the each of the three frequency regions can also be additive primary colors.

Our Eyes are Light Detectors!

Our eyes have two main types of photoreceptors called rods and cones. These cells are located in a layer at the back of the eye called the retina. Rods are used to see in very dim light and only show the world to us in black and white. This is why you see only black and white when you are outside in the evening or in a dimly lit room. The cones, allow us to see colors. They are not as sensitive as the rods so they only work in bright light.

There are three types of cones in the human eye.

Long wavelength cones with a peak detection of greenish-yellow. Medium wavelength cones with a peak detection of green .

Short wavelength cones that detect principally blue and violet colors.

Today you are being introduced to Analyzing Digital Images (ADI)

This is a digital photograph of blue and green light shining onto a screen

ADI has an interesting rectangle tool that can analyze what happens when colors of light are mixed.

The rectangle tool can also analyze what happens when paint colors are mixed.

How is the mixing of paints or pigments different from the mixing of colors of light?

How can you determine that a group of colors of paint are primary colors?

How can you determine that a group of colors of light are primary colors?