1. Chapter 7:- Color Space
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2. Topics: Introduction Definition of Color Colors Models Color Harmony
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3. Color Atoms produce unique colors as light passes through
Light travels in the form of photons, or quanta
Quantum Theory of Light (Max Planck 19th Century and 20th Century Niels Bohr – photons)
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4. Light and Spectra Light is an electromagnetic wave.
Its color is characterized by the wavelength content of the light.
Laser light consists of a single wavelength
Most light sources produce contributions over many wavelengths.
However, humans cannot detect all light, just contributions that fall in the “visible wavelengths”.
Short wavelengths produce a blue sensation, long wavelengths produce a red one.
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5. 1.Introduction
Wavelength of the light

6. How the Eye Sees Color
1. All the "invisible" colors of sunlight shine on the apple The surface of a red apple absorbs all the colored light rays, except for those corresponding to red, and reflects this color to the human eye The eye receives the reflected red light and sends a message to the brain.  
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7. Color
Cornea of your eye focuses light rays onto the retina to stimulate rods and cones which transmit the patterns of color information to the brain.
Cones are sensitive to red, green and blue light.
Green, blue, yellow. orange, purple, pink, brown black, gray and white are most common colors in all cultures.
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8. Things to know about COLOR:
Color is a way that we describe an object based on the way that it reflects or emits light.
Your eye can see different colors because a part of your eye called the retina is sensitive to different wavelengths of light.
The world’s most popular color is Blue
Red is the first color a baby sees.
Yellow + Red = Hunger
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9. Things to know about COLOR:
Men and women see the world differently
Anger management issues? Use pink!
What came first? The fruit or the color?
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10. Color Computerized color
Computers combine red, green, and blue (RGB) light
Bit depth determines the number of possible colors
1-bit 2 colors bit 16 colors 8-bit 256 colors bit 16,777,216 colors
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11. Color and Culture Western culture: Eastern culture
Red = anger, danger
Black = death
Eastern culture
Red = happiness
White = death
Internet study world's favorite color is blue
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12. Color – how you perceive it
Computer monitors produce color with red, green and blue light – the ADDITIVE primary colors. Tiny red, blue and green dots on the screen, light up when bombarded by electrons.
The reflected light from a printed page is SUBTRACTIVE primary colors ( cyan, magenta, yellow and a little black)
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13. Computerized Color
Most monitors today are set to display 640 X 480 pixels and 256 colors, can be adjusted for more
Called VGA ( Video Graphics Array)
Minimum configuration for Windows and MAC
More colors requires more memory
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15. Color Models 1- RGB 2- CMYK
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16. Color Models - RGB Additive Color: RGB
Describes colors that emanate from glowing bodies such as lights, TV, and computer monitors
In additive color models, mixing two colors results in a brighter color
Additive Colors  are created by mixing spectral light in varying combinations. The most common examples of this are television screens and computer monitors, which produce colored pixels by firing red, green, and blue electron guns at phosphors on the television or monitor screen.
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17. Color Models - RGB
Overlapping colors from 3 projectors produces new colors
Red + green -> yellow
Green + blue -> cyan
Red + blue -> magenta
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18. Color Models - RGB
RGB color space or RGB color system, constructs all the colors from the combination of the Red, Green and Blue colors.
The red, green and blue use 8 bits each, which have integer values from 0 to 255. This makes 256*256*256= possible colors.
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19. Color Models - RGB
The color systems used by scientists and artists are entirely different.
An artist will mix blue and yellow paint to get a shade of green.
A scientist will mix green and red light to create yellow. The printed page in a magazine is yet another system.
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20. Color Models - RGB
This color model is used in computer monitors, television sets, and theater. If you put your eye up against your television screen you might something like
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21. Color Models - CMYK Subtractive Color : CMYK
Most object reflect light
Mixing two colors creates a darker one
Similar to paint and printer's ink
Primary colors are cyan, magenta, yellow, which are complements of red, green and blue, respectively
Where 3 inks overlap, there is black ( gray)
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22. Color Models - CMYK
Subtractive colors are seen when pigments in an object absorb certain wavelengths of white light while reflecting the rest.
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23. Color Models - CMYK
CMYK is a subtractive, reflected light color system. All colors start with white "paper", to which different color "inks" are added to absorb (subtract) light that is reflected.
In theory, CMY are all you need to create black (applying all 3 colors at 100%). Alas, that usually results in a muddy, brownish black, so the addition of K (black) is added to the printing process. It also makes it easier to print black text
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24. Color Models - CMYK
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25. Color Models - CMYK
Below is an example of a photo originally produced in RGB colors converted to CMYK colors as displayed on a computer monitor. Notice how the colors are much more vibrant on the RGB picture.
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26. Color Models – RGB vs. CMYK
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27. Color Models – RGB vs CMYK
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28. Computer Color Models
Color of a pixel is expressed as the amount of red, green and blue ( RGB)
HSB ( hue, saturation, brightness) and HSL
( hue, saturation, lightness) models specify color as an angle from 0 –360 degrees on a color wheel and saturation, brightness, and lightness as percentages.
100% Lightness = white
Saturation is the intensity of the color Other color models are used for TV, photos and other media
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29. Computer Color Models
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30. Color Palettes
Palettes or color look up tables (CLUT) are mathematical tables that define the color of a pixel displayed on the screen
Paint programs provide a palette tools for displaying available colors – not uniform across programs or platforms
Color graphics adaptors work with 256 shades of each color producing over 16 million colors (256 x 256x 256)
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31. Color Models
Varying Brightness
Varying Saturation
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32. Color Harmony
Certain combinations of colors tend to be pleasing. They arise from the color harmony schemes:
Monochromatic
Complementary
Analogous
Triadic
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33. Primary Colors Secondary colors Tertiary Colors
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34. Color Harmony Schemes Primary colors: red, yellow and blue
Secondary colors: obtained by mixing two primary colors - orange violet, green
Tertiary colors: obtained by mixing equal amounts of a primary and secondary color - red-violet, blue- violet, blue-green, yellow-green, yellow-orange, red-orange
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35. Color Harmony Schemes
Warm (yellow, orange, red) or cool ( blue, green) colors
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36. Harmony Schemes- Monochromatic
all colors have hues that are the same or within a few degrees of one another
colors vary in saturation or brightness, but hue is consistent
enhances cohesiveness to overall layout of web page
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37. Monochromatic Examples
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38. Harmony Schemes-Complementary
uses a pair of complementary hues, which appear opposite one another on a color wheel
one color is dominant, the other is an accent
use the dominant hue to fill the large areas
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39. Complementary examples
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40. Harmony Schemes-Analogous
three colors which lie close together on a color wheel
often echo the colors found in nature
pleasing combinations ( such as orange, yellow, green)
more interesting if the colors do not have the same brightness and saturation
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41. Analogous examples
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42. Harmony Schemes-Triadic
Any 3 colors, spaced equally around a color wheel
Color hues form a triad
Offers wide variety of choice and can create excitement
Can be overpowering unless colors chosen vary in brightness and saturation, or the number of text and background are limited
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43. Triadic examples
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44. Triadic examples
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45. Color in Text and Background
Text should be legible
Contrast between text and background is important
Dark text on light background is best or one with high brightness and low saturation
Avoid combinations that differ only in their blue component ( yellow on white)
Avoid red-green, red-blue, magenta-green combinations which cause vibration and eye fatigue.
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46. Palette Flashing Problem
Palette Flashing occurs when you use a series of images each with its own color palette. When the new image replaces the older one a flash occurs on the screen - a serious problem in multimedia
Solution
use a single palette for all project images or
fade each image to white or black before showing the next image since white and black are present in most palettes
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47. Dithering
Dithering is a process where the color value of each pixel is changes to the closest matching color value in the target palette, using a mathematical algorithm
It “averages” the color over an area and is usually close to the original color
Dithering software is usually built into image editing and multimedia programs
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48. 1.Introduction Three Characteristics of Color: hue
brightness: the luminance of the object
saturation: the blue sky

49. The Foundation of Color
At its core, color is light.
Light is composed of many different colors and the various mixtures of light compose the colors that we can see.
To illustrate this point, the facilitator may want to discuss the differences in colors when viewed on a computer monitor versus colors viewed in print documents.

50. Colors that can not be created by mixing other colors)
Primary Colors
Colors that can not be created by mixing other colors)
Primary colors are a good way to introduce the categorizations for the various color types. First, as the name suggests, they are the building blocks for all the other colors. Additionally, thinking about red, blue, and yellow as the primary colors predates current color theory and is therefore an important historical aspect of the topic. Finally, many of us have been introduced to (and likely retained) this concept from basic art courses.
The primary colors are: red, blue, and yellow.

51. Colors made by mixing primary colors
Secondary Colors
Colors made by mixing primary colors
Secondary colors are created by mixing primaries. The secondary colors are purple, green, and orange.

52. Colors that mix primary and secondary colors
Tertiary Colors
Colors that mix primary and secondary colors
Tertiary colors are created by mixing primary and secondary colors.

53. Taken Together… The Color Wheel
This is only one way of representing the color wheel visually. There are a number of different visual interpretations of the color wheel that may be more effective for different people. More complex color wheels show even more colors and set up a way to read them that highlight even more complex relationships. These can easily be found through a Google search; however, this basic color wheel should effectively introduce the concept.

54. Using the Wheel
Colors are arranged on the wheel in such a way that purposeful color choices can be made.
Choices of color combination depend on what you are trying to accomplish.
Such as:
Contrast
Blending
Affect
The facilitator may want to revisit the question on which colors work well together after discussing the primary, secondary, and tertiary colors.

55. Using the Wheel
Complementary Colors are the colors opposite from one another on the wheel.
These colors provide the most visual contrast.
Contrast is the noticeable level of difference between two colors.
Designer can use the color wheel to determine color schemes for a number of media: documents (brochures, reports, etc.), websites, and slide presentations.