Understanding Color

Just a beginning!

By Beth Rajan Sockman

Additive & Subtractive

• Two colors most often used:– RGB = Additive Color• Add light get a LIGHTER image

– CYMK = Subtractive Color• More pigment added, the DARKER the image

Color Spaces

Click on image to link to movie about color space

Working with 3 Color Spaces

• RGB – Red, Green, Blue– Monitor– Light based devices (NOT SUNLIGHT!)

• CMY(K) – Cyan, Magenta, Yellow & Black– Print – Combine Pigments

• Pantone

RGB• Used on computer monitors,

digital cameras, televisions, mobile devices & other light-based devices

• Most PC allow 256 colors– 216 colors match on Mac® &

Windows® web-safe colors

100% Red + 100% Green + 100% Blue = White

RGB - Hexadecimal

• Remember this website: http://html-color-codes.com/

• Color codes are not in our number system which is the Decimal System or base 10. No, the numbers needed for any color code are written as Hexadecimals or base 16

RGB - Hexadecimal

• Decimal System:– 0 to 9 as in: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9

• Hexadecimal Number System uses 16 different digits before digits are combined: – 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F

RGB - Hexadecimal

• Once you go past "F", you combine the digits as in 10, 11, 12, etc. Here is the direct comparison between the two systems:

Decimal : 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18

Hexadecimal: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F, 10, 11, 12

RGB - Hexadecimal

• Intensity of each of the colors RED, GREEN and BLUE in a color code ranges from 0 to 255 (= a range of 256 numbers). – 0 is OFF meaning it contains no amount of the

color – 255 is FULL ON meaning full intensity of the color. – Since the code for each of the three colors must

be given as a Hexadecimal Code, the intensity for each color ranges from 0 to FF (Hex FF = Dec 255).

RGB

• What is the Hex Code for White?

• What is the Hex Code for Black?

FF, FF, FF

OO, OO, OO

CMYK

• CMYK color system is used for printed illustrations. It uses pigments as opposed to light.

• NOTICE the relationship between RGB & CMYK

R

B G

Pantone

• Propriety colors• Pigments were

developed in 1950’s• Include metallic and

various hues• SPOT COLOR– NO Mixing What you

select is what you get!

Hue & Saturation

Hue• Each individual color on

the color wheel

Saturation• Intensity of color from gray

tone to the pure color.

Theory

• Accessibility – – 8% of web audience will have color discrimination

challenges– Make colors contrast!

http://www.lighthouse.org/accessibility/design/accessible-print-design/effective-color-contrast

• Color Psychology – Colors evoke emotions

POWER ImpulsiveImpatienceSexual

JoyIntelligenceOrganizationHard to see!

TranquilityPatienceUnderstandingCooperation

HopeGrowthGood HealthFreshness

Review

• What model of color is used for light based devices?

• What do the hexadecimal numbers designate?

• (T/F) CMYK is in the same color space as RGB.

• (T/F) Pantone is a type of CMYK color.

• Is RED a Hue or Saturation?

RGB

Amount of RGB

FALSE

FALSE

HUE

References

• http://www.designworksoregon.com/pages/web_design_colors.html

• http://www.web-colors-explained.com/intro_web_colors.php

• http://evolt.org/Understanding_Color_and_Accessibility

• http://www.htmltutorials.ca/lesson9c.htm• http://www.lighthouse.org/accessibility/design/

accessible-print-design/effective-color-contrast• http://iit.bloomu.edu/vthc/design/hue.htm• http://www.youtube.com/watch?v=x0-

qoXOCOow&feature=player_embedded