1.
Rey San Andrew Rimando
BSCivil Engineering

2.
COLORS
 Is the VISUAL PERCEPTUAL PROPERTY
interacting in the eyes with the spectral
sensitivities of the light receptors in different
categories like RED, YELLOW, BLUE, GREEN,
ORANGE, VIOLET.
 Color categories and physical specifications
of color are also associated with objects,
materials, light sources, etc., based on their
physical properties such as light absorption,
reflection, or emission spectra.
 Color derives from the Spectrum of Light
(distribution of light powers versus
wavelength)

3.
Visible Light Spectrum; An
Introduction
Normally when we use the term "light," we are
referring to a type of electromagnetic wave that
stimulates the retina of our eyes. In this sense, we are
referring to visible light, a small spectrum from the
enormous range of frequencies of electromagnetic
radiation. This visible light region consists of a
spectrum of wavelengths that range from
approximately 700 nanometers (abbreviated nm) to
approximately 400 nm. Expressed in more familiar
units, the range of wavelengths extends from 7 x 10-7
meter to 4 x 10-7 meter. This narrow band of visible
light is affectionately known as ROYGBIV.
Each individual wavelength within the spectrum
of visible light wavelengths is representative of a
particular color. That is, when light of that particular
wavelength strikes the retina of our eye, we perceive
that specific color sensation.

4.
Color Vision in the Eye
Three types of cones (color)
One type of rod (B/W only)

5.
Sir Isaac Newton - DISPERSION
Showed that light shining through
a prism will be separated into its
different wavelengths and will thus
show the various colors that visible light
is comprised of. The separation of
visible light into its different colors is
known as dispersion.
Each color is characteristic of a
distinct wavelength; and different
wavelengths of light waves will bend
varying amounts upon passage
through a prism. For these reasons,
visible light is dispersed upon passage
through a prism. Dispersion of visible
light produces the colors red (R),
orange (O), yellow (Y), green (G), blue
(B), and violet (V). It is because of this
that visible light is sometimes referred to
as ROY G. BIV.
(Incidentally, the indigo is not actually observed
in the spectrum but is traditionally added to the
list so that there is a vowel in Roy's last name.)

6.
The red wavelengths of light are the longer wavelengths and the violet
wavelengths of light are the shorter wavelengths. Between red and violet, there
is a continuous range or spectrum of wavelengths.

7.
Wavelengths & Photons
Particles of light, called photons, each have a wavelength.
Red Photon
Yellow Photon
Green Photon
Blue Photon
Prism
Spectrum

8.
Additive Color Wheel
There are R
No Photons Spectral
of These Colors
Colors M Y
Red
B G
Yellow
Green
C Cyan
Blue
Magenta

9.
Adding Color Lights
Stream of
red & green photons
looks same as
yellow photons
(metamerism)
Eye to
Brain
or
Notice overlap of red, green, & blue
is seen as WHITE light
Theatrical lighting

10.
Newton’s Color Wheel
Prism spectrum is a
straight line, so why
did Isaac Newton
describe color using a
circular wheel?

11.
Before we continue our discussion,
Let me show you some tricks in Color Wheel

12.
The Color Wheel
 The color wheel is a
means of organizing
the colors in the
spectrum.
 The color wheel
consists of 12
sections, each
containing one hue.
 A hue is a name of
a color on the color
wheel.
 This lesson will discuss
each of the colors,
color harmonies and
how they are created.

13.
The Primary Color Triad
 The primary colors
yellow
are, red, yellow and
blue and are the
purest and most
intense of all the
colors.
The intensity of a color is
the brightness or dullness of red blue
a color.
They form a triangle on the
color wheel and are colors
that cannot be mixed from
any other colors. These are
the only colors that can be
found in nature.

14.
The Secondary Color Triad
 The secondary colors
are orange, green and
violet and are duller orange green
than the primaries
because they have
been mixed together.
 They form a triangle on
the color wheel and
are colors that are
mixed from the primary
colors.
 Primary + Primary =
secondary
Red + yellow=orange violet
Blue + yellow= green
Red + blue= violet

15.
The Intermediate (Tertiary) Colors
 These colors are yellow-orange,
yellow-green, blue-green, blue- Yellow
violet, red-orange, red-violet Yellow
orange green
and are even duller than the
secondary colors because the
primary has been mixed with a
secondary.
Red Blue
 These 6 colors are formed by
orange green
mixing a primary and a
secondary color.
 Primary + Secondary = Tertiary
Red Blue
yellow + orange=yellow-orange violet violet
red + orange = red-orange
red + violet =red-violet
blue + violet = blue-violet
blue + green =blue-green
yellow + green = yellow-green

16.
C
O
L
O
R
W
H
E
E
L

17.
Hue-Saturation Diagram
Eye is not a perfect
optical instrument.
Color “wheel” is
actually distorted
cone shape.
Rim is full saturation,
center is white
What color is
present in the
center?
ANS= WHITE

18.
Hue, Saturation, Value
Color wheel is
not
a single wheel
but
stack of wheels
that range in
value.

19.
The Warm and Cool Color Scheme
Warm colors range from:
yellow
yellow-orange
orange
red-orange
red
red-violet
Cool colors range from:
yellow-green
green
blue-green
blue
blue violet
violet

20.
Grayscale
A value scale is a scale of
grays running from black to
white.

21.
Spectral Reflectance Curves
When white light shines on a colored object, some photons
absorbed, others reflected by the object’s surface.

22.
Neutral Colors
Neutral Colors are those colors
not found on the color wheel
but are mixed by other colors
on the color wheel.
White
Brown
Gray
Black

23.
M
O
N
O
C
H
R
O
M
A
T
I
C
Having only one color. Here I used all shades of red to create the design

24.
A
N
A
L
O
G
O
U
S
Uses Colors that are next one another on the Color Wheel

25.
C
O
M
P
L
E
M
E
N
T
A
R
Y
Consists of colors that are opposite of one another on the color wheel.

26.
T
R
I
A
D
Consists of a color and the colors to the left and right of its complement

27.
Let’s do an example..
Let’s Try!

28.
Negative After-image
Stare, unfocused, at the red cross for 10 seconds then look at white wall

29.
Negative After-image
Cyan

30.
Negative After-image
Stare, unfocused, at the flag for 10 seconds then look at white wall

31.
Negative After-image
Cyan Magenta Yellow

32.
Simultaneous Contrast
Does the gray bar look slightly bluish?
Are the two gray bars the same shade of gray?
Yes, the presence of a nearby color affects perception of both
hue and value, shifting both towards complement