The source of colour 2

Level 2 Diploma in Painting and Decorating

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The source of colour

Unit 230: Creating and applying colour



Introduction

• Have you ever wondered what colour actually is?

• You may wonder why it is important to know. The answer is because it is the beginning of a fascinating journey on how colour influences our daily lives and should never be taken for granted.

• The following set of slides will explain where colour comes from and how it is actually seen.



Where does colour come from?Colour comes from light – white light to be exact. There are two sources of what we perceive as light:

•Artificial light: street lights, torches, household bulbs etc

•Natural light: daylight/sunlight

Colour comes from natural sunlight, which is commonly known as white light. The following slides explain how white light becomes colour.



You have probably heard of the term speed of light. How fast do you think it is?

•The speed of sound is 300 metres per second.

•The speed of light is 300,000km/s which is 1 million times faster

That is roughly the equivalent of flying around the world nearly eight times every second!

The speed of light



The colour spectrumIn order to be able to see colour, white light speed needs to be sloweddown. This can be done by transmitting it through a prism, which willthen reveal what is known as the colour spectrum.

GREEN

INDIGO

YELLOW

BLUE

RED

ORANGE

VIOLET

White light



Seeing colour – wavelengths

• Now you know what colour is and where it comes from, how do you actually see it?

• Colour travels in wavelengths in the white light. Although these colours travel at the same speed, they are different wavelengths and frequencies.

• Red is low frequency (long wavelength); blue is high frequency (short wavelength).



What are wavelengths and frequencies?

To explain these terms, think about picking up and flicking a long piece of rope – the slower you do it, the longer and less frequent the curves or ripples will be (low frequency/long waves).

Using more force and flicking it harder will result in shorter ripples arriving more frequently (high frequency/short waves). Radio waves and microwaves are delivered in the same way.



Warm and cool colour frequencies

Frequencies are directly related to colour.

• Cool colours are made up of high frequency wavelengths.

• Warm colours are made up of low frequency wavelengths.

230.6



Seeing colour • As the light lands on a surface, all the other coloured wavelengths

are absorbed into it except those that correspond to the actual properties of the surface itself.

• These are then reflected at different wavelengths to an area of the brain that interprets them as different colours.

• For instance, sunlight landing on a red surface:

230.7



Invisible colours

• Strange as it may sound, there are also colours that are invisible to the human eye in natural light. They can be found beyond either end of the colour spectrum.

• These cannot be seen* because the human brain is not able to process the frequency of their wavelengths.

• These two colours are infrared and ultraviolet.

* Unless you are a bee – they can actually see ultraviolet!!



Any questions?

Education

The source of colour 2