Write a short note on:

(a) colour addition

(b) colour subtraction

a) Colour addition:

 

 

The three primary colours are blue, green and red. 

From above diagram, the colour addition is as below

i) Red + Blue = Magenta 

ii) Red + Green = Yellow

iii) Blue +  Green = Cyan

 

Then the complementary colours are those combination of two light colours which gives white colour when mixed together. 

i) Magenta + Green = White

ii) Cyan + Red = White 

iii) Yellow + Blue = White 

 

b) Colour Subtraction: 

 

 

The rules of colour subtraction are as follows:

i) Red colour absorbs Green and blue and reflect red colour 

ii) Blue colour absorbs green and red and reflect blue colour 

iii) Green colour absorbs red and blue and reflect green colour 

iv) Cyan colour absorbs red and reflect blue green (Cyan) colour 

v) magenta colour absorbs green and reflect red + blue ( magenta) light

vi) yellow colour absorbs blue and reflect red green (yellow) light 

vii) black colour absorbs all colours and reflect no light.