How Do We Mix Color?How do determine complimentary color?

How Do We Mix Colored Light?• There are two types of color mixing:

1. The mixing of lights (additive). 2. The mixing of pigments (subtractive).

What are Additive Primary Colors?• Red, Green and Blue• Notice white in the center

Additive Primary Color Arithmetic

• Red + Green = Yellow • Green + Blue = Cyan• Red + Blue = Magenta

How Does Your Old TV Work?• Three electron beams strike three different

phosphors• At a distance you don’t notice the individual

colored dots

How Does Your Laptop Screen Work?• Each dot is a device or pixel is made up of 3

cells (Blue, Red and Green)• Light behind screen passes through the cell

or pixel to combine into one color

Laptop Screen Continued• The brightness of the three colors determines

the final color of the pixel• Instead of phosphors, the laptop uses a

Liquid Crystal Display (LCD)

How Do We Describe the Color White?• Primary additive + Secondary additive =

White; Considered Complimentary Colors• Blue + Yellow = White• Blue comes from 1/3 of the spectrum and

Yellow contains light from the other 2/3 of the spectrum (Red + Green)

Complimentary Color Arithmetic

• Secondary + Primary = White• Yellow + Blue = White• Magenta + Green = White• Cyan + Red = White

How Do We Determine Complimentary Colors from White Light?

• White – Primary = Secondary• White – Blue = Yellow• White – Red = Cyan• White – Green = Magenta

PRIMARY & SECONDARY ADDITIVE COLORS SMARTBOARD EXERCISE

Your Turn…

How Do We View Colored Objects in Colored Light?

Red

lightShirt looks red

Shorts look black

Blue

light

Shirt looks black

Shorts look blue

Object Color of light Color object seems to be

Red socksRed RedBlue BlackGreen Black

Blue teddyRed BlackBlueGreen

Green camelRedBlueGreen

Magenta book

RedBlueGreen

What are Subtractive Complimentary Colors

• Blocks and their shadows appear as different colors depending on the color of light that illuminates them.

What are Subtractive Complimentary Colors

• If white light falls on a pigment that absorbs red light, the light reflected appears cyan.

• Subtract a color from white light and you have the complementary color.

What are Subtractive Complimentary Colors

• White light passes through all three transparencies, the light of all frequencies is subtracted and black is produced

• Adding Cyan, Magenta and Yellow together will produce Black

COLOR MIXING WORKSHEETYour Turn…

Why Does Mixing Blue and Yellow Paint Give Us Green?

Color with Magazines and Newspaper • A printing press prints each

page with four different inks or pigments, CMYK (Cyan-Magenta-Yellow-Black)

• Each color is transferred to paper with a different plate

• The plate transfers tiny dots of color to the paper

• The overlapping dots plus black produce many colors

CMYK Printing

Homework

• Read pp. 554-558 • Answer Ques. 1, 2, 4, 26 .