Visible light - wavelengths 400nm (violet) to 700 nm (red) - 1 billionth of meter!
White light is mixture of all colors of visible spectrum
Black is total absence of light
Color perceived when visible light hits an object
and some wavelengths bounce through the pupils in our eyes causing
chemical reactions in our retina.
Retina filled
with 2 kinds of special cells: Rods and Cones. Each creates a unique
chemical reaction when light hits it and passes that info to our brain.
Rods let you see black and white & night vision. Can be damaged if eyes unprotected in bright light.
Cones let you
see color (distinguish 10 million colors!). In some people the cones
are not calibrated in the same way as the average person - these people
can be color deficient.
More info: www.eosweb.larc.nasa.gov (Atmospheric Science Data Center) www.hhmi.org (Howard Hughes Medical Institute)
Color Mixing
Primary colors
Red
Yellow
Blue
Secondary colors - mixture of 2 primary colors
Red + Yellow = Orange
Yellow + Blue = Green
Blue + Red = Violet (Purple)
Tertiary colors - mixture of 1 primary color and 1 secondary color
Red-Orange
Yellow-Orange
Yellow-Green
Blue-Green
Blue-Violet
Red -Violet
Hue - another name for color
Tint - add white
Tone - add gray
Shade - add black
Value - lightness or darkness of a color
Color Relationships
Monochromatic - Using one color (including shades, tints or tones)
Analogous - Using colors adjacent to each other on the color wheel
Complementary - Using colors opposite each other on the color wheel
Projects: Acrylic paints were used to make a color wheel consisting of primary, secondary and tertiary
colors. The students were given blue, yellow and red acrylic paint,
mixed them on a palette and transferred the resulting colors to a color
wheel template with q-tips (to avoid water rinsing). Everyone noticed
that the 'purple' was a little brown. This was because the 'blue'
pigment had a slight amount of yellow in it, so when mixed with red
resulted in a combination of all three primary colors. The kids noticed
that when all 3 are mixed, the result is brown.
We looked into this even further by purposely blending complementary
colors. Since a mix of colors opposite each other on the color wheel
will have varying amounts of all 3 primary colors the results will
always be a little 'earthier' or browner than the pure saturated colors.
There
was still excess paint on our palettes (sheets of wax paper!) and to
use up all the excess paint we scooped it up with Starbucks cards
(nicely donated by the Houghton Starbucks) and spread it onto a new
sheet of paper. We tried to spread only 2 colors at a time to avoid
brown and didn't over spread for the same reason. The results were some
very colorful, swirls of color which we can use later in collage or as
a background for another project.
We even saved the moist paper
towels that were used to mop up excess paint on our hands, table and
palette. When dry these 'tie dye' looking towels could also be used in
collage!