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Comparing Wavelengths of Red and Violet

Comparing Wavelengths of Red and Violet

This diagram compares the wavelength of two electromagnetic waves that correspond with an observer's perception of red and violet.
  • The diagram also looks at the units used when wavelength is being measured.
  • Notice that the wavelength of the red wave is much longer than the violet wave.
  • The wave cycle is measured from peak to peak and is marked by the dotted line.
  • The amplitude of both waves is the same.
  • Because the wavelength of the violet wave is shorter than the red its frequency is higher.
  • The unit of measurement of wavelength is the metre.
  • Because the ...
Overlapping Beams of Green and Blue Light Make Cyan

Overlapping Beams of Green and Blue Light Make Cyan

This is one of a set of 3 diagrams showing two torches project pairs of RGB primary colours onto a neutral coloured surface.
In this diagram green and blue primary colours overlap to produce cyan. Understanding the diagrams:
  • The diagrams illustrate how the RGB colour model works in practice.
  • The two primary colours have the same intensity.
  • Each torch points towards a different area of the surface so they overlap.
  • The light in each case is of a single wavelength so produces a spectral colour.
  • The selected wavelengths are: green = 525, blue = 460 nm.
...
Refraction of a Ray of Red Light

Refraction of a Ray of Red Light

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Overlapping Beams of Cyan, Magenta and Yellow

Overlapping Beams of Cyan, Magenta and Yellow

This diagram shows the effect of projecting cyan, magenta and yellow light onto a neutral coloured surface.
  • In the RGB colour model, cyan, magenta and yellow are secondary colours. Notice what colours are produced where they overlap!
  • Imagine that the three circles of colour (cyan, magenta and yellow) are produced by torches shining beams of light so they overlap one another.
  • Overlapping pairs of primary colours produce secondary colours.
  • But in this diagram overlapping pairs of secondary colours produce primary colours
  • The area where all three primary colours overlap is white.
Understanding the diagram
  • The diagrams illustrate ...
Sunlight Reflects off a Fish in Water

Sunlight Reflects off a Fish in Water

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RGB and HSB Colour Values

RGB and HSB Colour Values

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HSB Colour Model: Wedges

HSB Colour Model: Wedges

This diagram is a new addition to the site! More information will be added ASAP 🙂 ...
256 RGB Colours Between Cyan and Blue

256 RGB Colours Between Cyan and Blue

This is one of a series of six diagrams that together show all 1530 fully saturated colours in the RGB colour model. Fully saturated colours are produced by mixing two primary colours together.
Each diagram shows 256 colours starting with a primary and finishing with a secondary colour or visa-vera:
  • Red (primary colour) to yellow (secondary colour)
  • Yellow (secondary) to green (primary)
  • Green (primary) to cyan (secondary)
  • Cyan (secondary) to blue (primary)
  • Blue (primary) to magenta (secondary)
  • Magenta (secondary) to red (primary)
...
Comparing Frequencies of Red and Violet

Comparing Frequencies of Red and Violet

This diagram compares the frequency of two electromagnetic waves that correspond with an observer's perception of red and violet.
The diagram shows that the frequency of electromagnetic waves (light) refers to the number of oscillations that pass a given point in a given amount of time. Understanding the diagram
  • The diagram shows a total of three wave-cycles for red and eight wave-cycles for violet. The length of one wave-cycle (oscillation) is shown as a yellow arrow drawn on each wave.
  • The point at which measurement of passing waves is taken is shown as a vertical line below a clock face whilst the ...
Overlapping Beams of Blue and Red Light Make Magenta

Overlapping Beams of Blue and Red Light Make Magenta

This is one of a set of 3 diagrams showing two torches project pairs of RGB primary colours onto a neutral coloured surface.
In this diagram blue and red primary colours overlap to produce magenta. Understanding the diagrams:
  • The diagrams illustrate how the RGB colour model works in practice.
  • The two primary colours have the same intensity.
  • Each torch points towards a different area of the surface so they overlap.
  • The light in each case is of a single wavelength so produces a spectral colour.
  • The selected wavelengths are: red = 660 nanometres (nm), blue = 460 nm.
  • ...
Actual and Observed Position of an Object in Water

Actual and Observed Position of an Object in Water

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Adding RGB Colours between Primaries

Adding RGB Colours between Primaries

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Refraction, Reflection and Total Internal Reflection

Refraction, Reflection and Total Internal Reflection

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HSB Colour Model: Hue and Saturation

HSB Colour Model: Hue and Saturation

This diagram is a new addition to the site! More information will be added ASAP 🙂 ...
Greyscale: Disks

Greyscale: Disks

This diagram is a new addition to the site! More information will be added ASAP 🙂 ...
RGB Colour Picker: Cyan to Blue

RGB Colour Picker: Cyan to Blue

This is one of a series of six colour pickers that together show all 1530 fully saturated RGB colours along with their codes. Fully saturated colours are produced by mixing two primary colours together.
Each diagram shows 256 colours starting with a primary and finishing with a secondary colour or visa-vera:
  • Red (primary colour) to yellow (secondary colour)
  • Yellow (secondary) to green (primary)
  • Green (primary) to cyan (secondary)
  • Cyan (secondary) to blue (primary)
  • Blue (primary) to magenta (secondary)
  • Magenta (secondary) to red (primary)
...
Wavelength and the Electromagnetic Spectrum

Wavelength and the Electromagnetic Spectrum

This diagram shows that the electromagnetic spectrum includes waves with all possible wavelengths of radiation.
Notice that:
  • Wavelengths range from low energy radio waves through visible light to high energy gamma rays.
  • Waves with longer wavelengths have a lower frequency and carry less energy.
  • Waves with shorter wavelengths have a higher frequency and carry more energy.
Remember that:
  • The electromagnetic spectrum includes, in order of increasing frequency and decreasing wavelength: radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, X-rays and gamma rays.
  • There are no precisely defined boundaries between the bands of electromagnetic radiation ...
RGB Colour and Spectral Colour

RGB Colour and Spectral Colour

This diagram is a new addition to the site! More information will be added ASAP 🙂 ...
Electric and Magnetic Properties of Light

Electric and Magnetic Properties of Light

This diagram shows that an electromagnetic wave (lightwave) results from the interaction of an electric and magnetic field.
  • Electromagnetic waves are produced by the Sun as a result of thermonuclear fusion.
  • The explosive force of thermonuclear fusion is caused by gravity crushing hydrogen atoms until they collapse.
  • The nuclear reaction forces hydrogen atoms to combine into helium atoms and release vast amounts of electrical and magnetic energy.
  • The electrical and magnetic forces form fields which interact with each other to produce a wave pattern that radiates out into space at the speed of light.
  • The electromagnetic waves are of ...
RGB Colour Wheel with 3 Colours

RGB Colour Wheel with 3 Colours

This is one of a series of diagrams exploring RGB colour wheels. Colour wheels demonstrate or simulate the effect of colour mixing.
Colour wheels can be used to explore the effect of mixing any type of colour. Light, inks, dyes, artist's paints, pigments and colourants all produce other colours when mixed together. Whilst a colour model outlines a method for mixing and using different types of colour, a colour wheel explores what happens in practice ...
Using RGB Colour to Mix Wavelengths of Light

Using RGB Colour to Mix Wavelengths of Light

This diagram explores the RGB colour model. It looks at how wavelengths of light corresponding with the RGB primary colours are combined to produce secondary colours.
What you need to remember:
  • Mixing different wavelengths of light to produce other colours, is called an additive colour model or an additive approach to colour.
  • Red, green and blue (RGB) are additive primary colours. This means that when these wavelengths of light are projected onto a dark surface they combined to produce other colours.
  • If wavelengths of light corresponding with all three additive primary colours are projected in equal amounts onto ...
HSB Colour Model: Hue and Brightness

HSB Colour Model: Hue and Brightness

This diagram is a new addition to the site! More information will be added ASAP 🙂 ...
Greyscale: Disks

Greyscale: Disks

This diagram is a new addition to the site! More information will be added ASAP 🙂 ...
256 RGB Colours Between Blue and Magenta

256 RGB Colours Between Blue and Magenta

This is one of a series of six diagrams that together show all 1530 fully saturated colours in the RGB colour model. Fully saturated colours are produced by mixing two primary colours together.
Each diagram shows 256 colours starting with a primary and finishing with a secondary colour or visa-vera:
  • Red (primary colour) to yellow (secondary colour)
  • Yellow (secondary) to green (primary)
  • Green (primary) to cyan (secondary)
  • Cyan (secondary) to blue (primary)
  • Blue (primary) to magenta (secondary)
  • Magenta (secondary) to red (primary)
...
Frequency of Electromagnetic Waves

Frequency of Electromagnetic Waves

This diagram looks at the frequency of electromagnetic waves.
  • It shows that the frequency of electromagnetic radiation (light) refers to the number of wave-cycles of an electromagnetic wave that pass a given point in a given amount of time.
  • The frequency of an electromagnetic wave can be thought about in the same way as the frequency of trains that pass through a railway station. If a train passes through a station every 10 minutes then the frequency is six trains per hour.
Remember that:
  • The frequency of a wave should not be confused with the speed at ...
Refraction of a Ray of Light Towards the Normal

Refraction of a Ray of Light Towards the Normal

This diagram is a new addition to the site! More information will be added ASAP 🙂

...
Long Waves to Short Waves

Long Waves to Short Waves

This diagram shows six electromagnetic waves. Each wave corresponds with a colour within the visible spectrum that an observer might recognise.
Remember that:
  • Electromagnetic waves, which are a form of electromagnetic radiation, propagating from a light source, travel through space and encounter different materials.
  • Colour is not a property of electromagnetic radiation, but an aspect of visual perception.
  • A human observer can distinguish between colours corresponding with many thousands of wavelengths of light in the visible spectrum. These colours are often called spectral colours.
  • The largest part of the electromagnetic spectrum is outside the wavelengths of visible light ...
RGB Colour Wheel with 6 Colours

RGB Colour Wheel with 6 Colours

This is one of a series of diagrams exploring RGB colour wheels. Colour wheels demonstrate or simulate the effect of colour mixing.
Colour wheels can be used to explore the effect of mixing any type of colour. Light, inks, dyes, artist's paints, pigments and colourants all produce other colours when mixed together. Whilst a colour model outlines a method for mixing and using different types of colour, a colour wheel explores what happens in practice ...
RGB Additive Colour Model

RGB Additive Colour Model

This diagram introduces the RGB colour model. It shows the three primary colours (red, green and blue) with secondary colours between them. What you need to remember:
  • Mixing different wavelengths of light to produce other colours, is called an additive colour model or an additive approach to colour.
  • Red, green and blue (RGB) are additive primary colours. This means that when these wavelengths of light are projected onto a dark surface they combined to produce other colours. The colour produced depends on the intensity of each light source.
  • If wavelengths of light corresponding with all three additive primary ...
HSB Colour Model: Hue and Saturation

HSB Colour Model: Hue and Saturation

This diagram is a new addition to the site! More information will be added ASAP 🙂 ...
256 RGB Colours: Red to Yellow

256 RGB Colours: Red to Yellow

This is one of a series of six diagrams that together show all 1530 fully saturated colours in the RGB colour model. Fully saturated colours are produced by mixing two primary colours together.
Each diagram shows 256 colours starting with a primary and finishing with a secondary colour or visa-vera:
  • Red (primary colour) to yellow (secondary colour)
  • Yellow (secondary) to green (primary)
  • Green (primary) to cyan (secondary)
  • Cyan (secondary) to blue (primary)
  • Blue (primary) to magenta (secondary)
  • Magenta (secondary) to red (primary)
...
RGB Colour Picker: Blue to Magenta

RGB Colour Picker: Blue to Magenta

This is one of a series of six colour pickers that together show all 1530 fully saturated RGB colours along with their codes. Fully saturated colours are produced by mixing two primary colours together.
Each diagram shows 256 colours starting with a primary and finishing with a secondary colour or visa-vera:
  • Red (primary colour) to yellow (secondary colour)
  • Yellow (secondary) to green (primary)
  • Green (primary) to cyan (secondary)
  • Cyan (secondary) to blue (primary)
  • Blue (primary) to magenta (secondary)
  • Magenta (secondary) to red (primary)
...
Why an Object Appears Magenta in Sunlight

Why an Object Appears Magenta in Sunlight

This is one of a set of 10 diagrams exploring why objects appear to be different colours to an observer.
There are always three key factors that affect the colour of an object.
  • The first is the type of light source and what happens to the light on its journey towards an object.
  • The second is what happens when light strikes different types of objects and materials.
  • The third concerns factors related to the observer which affect what they see and how things appear.
...
Refraction of a Ray of Light Away from the Normal

Refraction of a Ray of Light Away from the Normal

This diagram is a new addition to the site! More information will be added ASAP 🙂

...
Why an Object Appears White in Sunlight

Why an Object Appears White in Sunlight

This is one of a set of 10 diagrams exploring why objects appear to be different colours to an observer.
There are always three key factors that affect the colour of an object.
  • The first is the type of light source and what happens to the light on its journey towards an object.
  • The second is what happens when light strikes different types of objects and materials.
  • The third concerns factors related to the observer which affect what they see and how things appear.
...
RGB Colour Wheel with 6 Colours

RGB Colour Wheel with 6 Colours

This is one of a series of diagrams exploring RGB colour wheels. Colour wheels demonstrate or simulate the effect of colour mixing.
Colour wheels can be used to explore the effect of mixing any type of colour. Light, inks, dyes, artist's paints, pigments and colourants all produce other colours when mixed together. Whilst a colour model outlines a method for mixing and using different types of colour, a colour wheel explores what happens in practice ...
CMY Subtractive Colour Model

CMY Subtractive Colour Model

This diagram introduces the CMY colour model. It shows the three primary colours (cyan, magenta and blue) with secondary colours between them.
The CMY colour model is a subtractive colour model that predicts the appearance of cyan, magenta and yellow inks when they are mixed together to produce other colours. What you need to remember:
  • The CMY colour model is a method for mixing inks used by digital printers to produce other colours. It is called a subtractive colour model (a subtractive approach to colour).
  • The name of the CMY colour model comes from the initials of its ...
HSB Colour Model: Hue and Brightness

HSB Colour Model: Hue and Brightness

This diagram is a new addition to the site! More information will be added ASAP 🙂 ...
256 RGB Colours: Yellow to Green

256 RGB Colours: Yellow to Green

This is one of a series of six diagrams that together show all 1530 fully saturated colours in the RGB colour model. Fully saturated colours are produced by mixing two primary colours together.
Each diagram shows 256 colours starting with a primary and finishing with a secondary colour or visa-vera:
  • Red (primary colour) to yellow (secondary colour)
  • Yellow (secondary) to green (primary)
  • Green (primary) to cyan (secondary)
  • Cyan (secondary) to blue (primary)
  • Blue (primary) to magenta (secondary)
  • Magenta (secondary) to red (primary)
...
256 RGB Colours Between Magenta and Red

256 RGB Colours Between Magenta and Red

This is one of a series of six diagrams that together show all 1530 fully saturated colours in the RGB colour model. Fully saturated colours are produced by mixing two primary colours together.
256 RGB Colours Between Magenta and RedEach diagram shows 256 colours starting with a primary and finishing with a secondary colour or visa-vera:
  • Red (primary colour) to yellow (secondary colour)
  • Yellow (secondary) to green (primary)
  • Green (primary) to cyan (secondary)
  • Cyan (secondary) to blue (primary)
  • Blue (primary) to magenta (secondary)
  • Magenta (secondary) to red (primary)
...
Sensitivity of Eye to the Colour Spectrum (svg) 11000-0-A-BL-EN

Sensitivity of Eye to the Colour Spectrum

This diagram is a new addition to the site! More information will be added ASAP 🙂

...
The Law of Refraction Explained

The Law of Refraction Explained

This diagram is a new addition to the site! More information will be added ASAP 🙂

...
Why an Object Appears Orange in Sunlight

Why an Object Appears Orange in Sunlight

This is one of a set of 10 diagrams exploring why objects appear to be different colours to an observer.
There are always three key factors that affect the colour of an object.
  • The first is the type of light source and what happens to the light on its journey towards an object.
  • The second is what happens when light strikes different types of objects and materials.
  • The third concerns factors related to the observer which affect what they see and how things appear.
...
RGB Colour Wheel with 18 Colours

RGB Colour Wheel with 18 Colours

This is one of a series of diagrams exploring RGB colour wheels. Colour wheels demonstrate or simulate the effect of colour mixing.
Colour wheels can be used to explore the effect of mixing any type of colour. Light, inks, dyes, artist's paints, pigments and colourants all produce other colours when mixed together. Whilst a colour model outlines a method for mixing and using different types of colour, a colour wheel explores what happens in practice ...
RYB Subtractive Colour Model

RYB Subtractive Colour Model

This diagram introduces the RYB colour model. It shows the three primary colours (red, yellow and blue) with secondary colours between them.
The RYB colour model is a subtractive colour model that predicts the appearance of red, yellow and blue paints and opaque pigments when they are mixed together to produce other colours. What you need to remember:
  • The RYB colour model is a method for mixing different artists paints and opaque pigments to produce other colours. It is called a subtractive colour model (a subtractive approach to colour).
  • The name of the RYB colour model comes from ...
RGB and HSB Colour Values

RGB and HSB Colour Values

This diagram is a new addition to the site! More information will be added ASAP 🙂 ...
256 RGB Colours: Green to Cyan

256 RGB Colours: Green to Cyan

This is one of a series of six diagrams that together show all 1530 fully saturated colours in the RGB colour model. Fully saturated colours are produced by mixing two primary colours together.
Each diagram shows 256 colours starting with a primary and finishing with a secondary colour or visa-vera:
  • Red (primary colour) to yellow (secondary colour)
  • Yellow (secondary) to green (primary)
  • Green (primary) to cyan (secondary)
  • Cyan (secondary) to blue (primary)
  • Blue (primary) to magenta (secondary)
  • Magenta (secondary) to red (primary)
...
RGB Colour Picker: Magenta to Red

RGB Colour Picker: Magenta to Red

This is one of a series of six colour pickers that together show all 1530 fully saturated RGB colours along with their codes. Fully saturated colours are produced by mixing two primary colours together.
Each diagram shows 256 colours starting with a primary and finishing with a secondary colour or visa-vera:
  • Red (primary colour) to yellow (secondary colour)
  • Yellow (secondary) to green (primary)
  • Green (primary) to cyan (secondary)
  • Cyan (secondary) to blue (primary)
  • Blue (primary) to magenta (secondary)
  • Magenta (secondary) to red (primary)
...
Response of the Cone Cells in the Human Eye to Colour (svg) 11010-0-A-BL-EN

Response of the Cone Cells in the Human Eye to Colour

This diagram is a new addition to the site! More information will be added ASAP 🙂 ...
Refractive Index Explained

Refractive Index Explained

This diagram is a new addition to the site! More information will be added ASAP 🙂

...
Why-an-Object-Appears-Green-in-Sunlight (svg) 02000-0-A-BL-EN

Why an Object Appears Green in Sunlight

This is one of a set of 10 diagrams exploring why objects appear to be different colours to an observer.
There are always three key factors that affect the colour of an object.
  • The first is the type of light source and what happens to the light on its journey towards an object.
  • The second is what happens when light strikes different types of objects and materials.
  • The third concerns factors related to the observer which affect what they see and how things appear.
...
RGB Colour Wheel with 18 Colours

RGB Colour Wheel with 18 Colours

This is one of a series of diagrams exploring RGB colour wheels. Colour wheels demonstrate or simulate the effect of colour mixing.
Colour wheels can be used to explore the effect of mixing any type of colour. Light, inks, dyes, artist's paints, pigments and colourants all produce other colours when mixed together. Whilst a colour model outlines a method for mixing and using different types of colour, a colour wheel explores what happens in practice ...
Paths of Red Green and Blue Rays in a Raindrop

Paths of Red Green and Blue Rays in a Raindrop

This diagram is a new addition to the site! More information will be added ASAP 🙂 ...
Hue and Greyscale

Hue and Greyscale

This diagram is a new addition to the site! More information will be added ASAP 🙂 ...
256 RGB Colours: Cyan to Blue

256 RGB Colours: Cyan to Blue

This is one of a series of six diagrams that together show all 1530 fully saturated colours in the RGB colour model. Fully saturated colours are produced by mixing two primary colours together.
Each diagram shows 256 colours starting with a primary and finishing with a secondary colour or visa-vera:
  • Red (primary colour) to yellow (secondary colour)
  • Yellow (secondary) to green (primary)
  • Green (primary) to cyan (secondary)
  • Cyan (secondary) to blue (primary)
  • Blue (primary) to magenta (secondary)
  • Magenta (secondary) to red (primary)
...
1530 RGB Colours

1530 RGB Colours

This diagram shows all 1530 fully saturated colours in the RGB colour model. Fully saturated colours are produced by mixing two primary colours together.
The diagram splits the total of 1530 into blocks of 256 colours with each block starting with a primary and finishing with a secondary colour or visa-vera. The six segments are:
  • Red (primary colour) to yellow (secondary colour)
  • Yellow (secondary) to green (primary)
  • Green (primary) to cyan (secondary)
  • Cyan (secondary) to blue (primary)
  • Blue (primary) to magenta (secondary)
  • Magenta (secondary) to red (primary)
...
Wavelengths from Red to Violet

Wavelengths from Red to Violet

This diagram is about which wavelengths of electromagnetic radiation correspond with the different colours we see in the world.
The important fact to remember is that the wavelengths of light within the visible spectrum correspond with all the colours that we see between red and violet.
  • The white arrows in the diagram show the Sun emitting sunlight at all wavelengths of the visible spectrum.
  • The term white light is used when all colours of the visible spectrum are mixed together.
  • The spectrum of colours between red and violet illustrates that although an observer will often describe visible light ...
Combining Red, Green and Blue Light

Combining Red, Green and Blue Light

This diagram explains what happens when red, green and blue primary colours are projected onto a dark surface so that they overlap.
What you need to remember:
  • Mixing different wavelengths of light to produce other colours, is called an additive colour model or an additive approach to colour.
  • Red, green and blue (RGB) are additive primary colours. This means that when these wavelengths of light are projected onto a dark surface they combined to produce other colours.
  • If wavelengths of light corresponding with all three additive primary colours are projected in equal amounts onto a dark surface the ...
Chromatic Dispersion of a Ray of White Light

Chromatic Dispersion of a Ray of White Light

This diagram is a new addition to the site! More information will be added ASAP 🙂 ...
Why an Object Appears Blue in Sunlight

Why an Object Appears Blue in Sunlight

This is one of a set of 10 diagrams exploring why objects appear to be different colours to an observer.
There are always three key factors that affect the colour of an object.
  • The first is the type of light source and what happens to the light on its journey towards an object.
  • The second is what happens when light strikes different types of objects and materials.
  • The third concerns factors related to the observer which affect what they see and how things appear.
...
RGB Colour Wheel with 30 Colours

RGB Colour Wheel with 30 Colours

This is one of a series of diagrams exploring RGB colour wheels. Colour wheels demonstrate or simulate the effect of colour mixing.
Colour wheels can be used to explore the effect of mixing any type of colour. Light, inks, dyes, artist's paints, pigments and colourants all produce other colours when mixed together. Whilst a colour model outlines a method for mixing and using different types of colour, a colour wheel explores what happens in practice ...
How to See a Rainbow

How to See a Rainbow

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RGB Colour Wheels with 3 to 102 Colours

RGB Colour Wheels with 3 to 102 Colours

This diagram is a new addition to the site! More information will be added ASAP 🙂 ...
256 RGB Colours: Blue to Magenta

256 RGB Colours: Blue to Magenta

This is one of a series of six diagrams that together show all 1530 fully saturated colours in the RGB colour model. Fully saturated colours are produced by mixing two primary colours together.
Each diagram shows 256 colours starting with a primary and finishing with a secondary colour or visa-vera:
  • Red (primary colour) to yellow (secondary colour)
  • Yellow (secondary) to green (primary)
  • Green (primary) to cyan (secondary)
  • Cyan (secondary) to blue (primary)
  • Blue (primary) to magenta (secondary)
  • Magenta (secondary) to red (primary)
...
HSB Greyscale: Wedges

HSB Greyscale: Wedges

This diagram is a new addition to the site! More information will be added ASAP 🙂 ...
The Visible Spectrum

The Visible Spectrum

This diagram is about sunlight, the visible spectrum and which wavelengths of electromagnetic radiation correspond with the different colours we see in the world.
The diagram shows that wavelengths of light within the visible spectrum correspond with the different colours we see in the world. Notice that:
  • The white arrows in the diagram represent the Sun emitting sunlight at every wavelength of the visible spectrum.
  • The term white light is used when all colours of the visible spectrum are mixed together.
  • The coloured arrows represent six bands of wavelengths of visible light corresponding with red, orange, yellow, green, ...
Spectral Colour and the RGB Colour Model

Spectral Colour and the RGB Colour Model

This diagram shows six spectral colours, red, orange, yellow, green, blue and violet. 
  • Spectral colours are produced by a single wavelength of light.
  • Some spectral colours can also be produced by mixing two wavelengths of light together.
Understanding the diagram:
  • Above the line of coloured circles are the wavelengths of light that produce each spectral colour.
  • Of the six colours (ROYGBV), red, green and blue can only be produced by a single wavelength of light.
  • The other three spectral colours, orange, yellow and violet, can be produced either by a single wavelength of light or by additive ...
Chromatic Dispersion of Red Green and Blue Wavelengths

Chromatic Dispersion of Red Green and Blue Wavelengths

This diagram is a new addition to the site! More information will be added ASAP 🙂 ...
Why an Object Appears Violet in Sunlight

Why an Object Appears Violet in Sunlight

This is one of a set of 10 diagrams exploring why objects appear to be different colours to an observer.
There are always three key factors that affect the colour of an object.
  • The first is the type of light source and what happens to the light on its journey towards an object.
  • The second is what happens when light strikes different types of objects and materials.
  • The third concerns factors related to the observer which affect what they see and how things appear.
...
RGB Colour Wheel with 30 Colours

RGB Colour Wheel with 30 Colours

This is one of a series of diagrams exploring RGB colour wheels. Colour wheels demonstrate or simulate the effect of colour mixing.
Colour wheels can be used to explore the effect of mixing any type of colour. Light, inks, dyes, artist's paints, pigments and colourants all produce other colours when mixed together. Whilst a colour model outlines a method for mixing and using different types of colour, a colour wheel explores what happens in practice ...
Human Eye in Cross Section

Human Eye in Cross Section

This diagram is a new addition to the site! More information will be added ASAP 🙂 ...
Colours Between RGB Primaries

Colours Between RGB Primaries

This diagram is a new addition to the site! More information will be added ASAP 🙂 ...
256 RGB Colours: Magenta to Red

256 RGB Colours: Magenta to Red

This is one of a series of six diagrams that together show all 1530 fully saturated colours in the RGB colour model. Fully saturated colours are produced by mixing two primary colours together.
Each diagram shows 256 colours starting with a primary and finishing with a secondary colour or visa-vera:
  • Red (primary colour) to yellow (secondary colour)
  • Yellow (secondary) to green (primary)
  • Green (primary) to cyan (secondary)
  • Cyan (secondary) to blue (primary)
  • Blue (primary) to magenta (secondary)
  • Magenta (secondary) to red (primary)
...
Facts about the Sun

Facts about the Sun

This diagram introduces the Sun, the star at the centre of our solar system. It lists some useful facts that help explain why it is so important in our lives.
Remember that:
  • The sun is unlike anything else in our experience. Its age, size, temperature are all on a scale apart from life on planet Earth.
  • It explodes with the force of a billion one-megaton nuclear bombs every single second of every single day.
  • Without the energy produced by the sun, life as we know it would not be possible.
...
Facts about White Light

Facts about White Light

This diagram introduces white light, the name given to light that contains all wavelength of the visible spectrum.
Remember that:
  • White light contains all the wavelengths of the visible spectrum.
  • White light contains all wavelengths of light that correspond with the colours of the rainbow.
  • White light does not include infrared and ultraviolet wavelengths of light.
...
Spectral and RGB Colour

Spectral and RGB Colour

This diagram shows the six spectral colours associated with the colours of the rainbow.
  • The top half of the diagram shows that each of these spectral colours can be produced by a single wavelength of light.
  • The bottom half of the diagram shows that three spectral colours (red, green and blue) can be combined in pairs to produce orange, yellow and violet.
Remember that:
  • Spectral colours are produced by a single wavelength of light. So each individual wavelength of visible light produces a different spectral colour.
  • Rainbows are produced by spectral colours as sunlight is refracted and ...
Reflection of a Ray of Light

Reflection of a Ray of Light

This diagram is a new addition to the site! More information will be added ASAP 🙂 ...
Why an Object Appears Yellow in Sunlight

Why an Object Appears Yellow in Sunlight

This is one of a set of 10 diagrams exploring why objects appear to be different colours to an observer.
There are always three key factors that affect the colour of an object.
  • The first is the type of light source and what happens to the light on its journey towards an object.
  • The second is what happens when light strikes different types of objects and materials.
  • The third concerns factors related to the observer which affect what they see and how things appear.
...
RGB Colour Wheel with 102 Colours

RGB Colour Wheel with 102 Colours

This is one of a series of diagrams exploring RGB colour wheels. Colour wheels demonstrate or simulate the effect of colour mixing.
Colour wheels can be used to explore the effect of mixing any type of colour. Light, inks, dyes, artist's paints, pigments and colourants all produce other colours when mixed together. Whilst a colour model outlines a method for mixing and using different types of colour, a colour wheel explores what happens in practice ...
Retina of the Human Eye in Detail

Retina of the Human Eye in Detail

This diagram is a new addition to the site! More information will be added ASAP 🙂 ...
Adding Colours Between RGB Primaries

Adding Colours Between RGB Primaries

This diagram is a new addition to the site! More information will be added ASAP 🙂 ...
1530 RGB Colours

1530 RGB Colours

This diagram shows all 1530 fully saturated colours in the RGB colour model. Fully saturated colours are produced by mixing two primary colours together.
The diagram splits the total of 1530 into blocks of 256 colours with each block starting with a primary and finishing with a secondary colour or visa-vera. The six segments are:
  • Red (primary colour) to yellow (secondary colour)
  • Yellow (secondary) to green (primary)
  • Green (primary) to cyan (secondary)
  • Cyan (secondary) to blue (primary)
  • Blue (primary) to magenta (secondary)
  • Magenta (secondary) to red (primary)
...
Spectral Colour Model

Spectral Colour Model

This diagram introduces the spectral colour model. Spectral colours are the colours of the visible spectrum.
Spectral colours are evoked by a single wavelength of light in the visible spectrum. So, very wavelength of visible light is perceived as a spectral colour by a human observer. The spectral colour model explains why different light sources produce different experiences of colour for an observer. What you need to remember:
  • A diagram of spectral colour is usually presented in the form of a continuous linear spectrum organised by wavelength, with red at one end and violet at the other.
  • The ...
Facts about Sunlight

Facts about Sunlight

This diagram introduces sunlight, the light produced by the Sun, the star at the centre of our solar system.
It gathers together some useful facts and introduces some important terms that you can check out in the next section. Remember that:
  • As the Sun explodes with the force of a billion one-megaton nuclear bombs every second it gives off electromagnetic radiation.
  • Sunlight is a form of electromagnetic radiation.
  • The electromagnetic radiation given off by the sun includes all wavelengths of the electromagnetic spectrum.
  • By the time sunlight has passed through the atmosphere and reaches the ground it contains ...
The Human Eye and RGB Colour

The Human Eye and RGB Colour

This diagram is about the perception of colour. It explores how our eyes respond to wavelengths of light corresponding with red, green and blue.
  • As we look at the world on a sunny day a vast range of wavelengths of visible light enter our eyes. Each wavelength corresponds with the perception of a different spectral colour.
  • When wavelengths of light corresponding with only red, green and blue enter the eye in different proportions, our eyes are still able to see a full gamut of colours.
  • The colours we see when wavelengths corresponding with just red, green and blue light ...
Reflection and Refraction at a Curved Boundary

Reflection and Refraction at a Curved Boundary

This diagram is a new addition to the site! More information will be added ASAP 🙂 ...
Why an Object Appears Cyan in Sunlight

Why an Object Appears Cyan in Sunlight

This is one of a set of 10 diagrams exploring why objects appear to be different colours to an observer.
There are always three key factors that affect the colour of an object.
  • The first is the type of light source and what happens to the light on its journey towards an object.
  • The second is what happens when light strikes different types of objects and materials.
  • The third concerns factors related to the observer which affect what they see and how things appear.
...
Colour-Wheel-with-102-Colours (svg) 05300-3-A-BL-EN-RGB

RGB Colour Wheel with 102 Colours

This is one of a series of diagrams exploring RGB colour wheels. Colour wheels demonstrate or simulate the effect of colour mixing.
Colour wheels can be used to explore the effect of mixing any type of colour. Light, inks, dyes, artist's paints, pigments and colourants all produce other colours when mixed together. Whilst a colour model outlines a method for mixing and using different types of colour, a colour wheel explores what happens in practice ...
Human Eye Eyeball and Retina

Human Eye Eyeball and Retina

This diagram is a new addition to the site! More information will be added ASAP 🙂 ...
Mixing Primary Colours in Different Proportions

Mixing Primary Colours in Different Proportions

This diagram is a new addition to the site! More information will be added ASAP 🙂 ...
256 RGB Colours Between Red and Yellow

256 RGB Colours Between Red and Yellow

This is one of a series of six diagrams that together show all 1530 fully saturated colours in the RGB colour model. Fully saturated colours are produced by mixing two primary colours together.
Each diagram shows 256 colours starting with a primary and finishing with a secondary colour or visa-vera:
  • Red (primary colour) to yellow (secondary colour)
  • Yellow (secondary) to green (primary)
  • Green (primary) to cyan (secondary)
  • Cyan (secondary) to blue (primary)
  • Blue (primary) to magenta (secondary)
  • Magenta (secondary) to red (primary)
...
Refraction of Light Towards the Normal

Refraction of Light Towards the Normal

This diagram is a new addition to the site! More information will be added ASAP 🙂 ...
Bands of Colour from Red to Violet

Bands of Colour from Red to Violet

This diagram is about the fact that wavelengths of light within the visible spectrum often appear to form bands of colour.
  • Every wavelength of electromagnetic radiation (light) corresponds with a different colour we see in the world.
  • When an observer sees a continuous range of wavelengths they see bands of colour.
  • When all wavelengths within the visible spectrum are present an observer will often see six bands of colour - the colours of the rainbow, ROYGBV.
  • The list on the left of the diagram shows the range of wavelengths corresponding with each band of colour.
Remember that: ...
Red light Projected onto a Dark Surface

Red light Projected onto a Dark Surface

This is one of a set of 3 diagrams showing torches projecting red, green and blue light onto a neutral coloured surface.
A fourth diagram shows what happens when all three torches are turned on at the same time and their beams partially overlap one another. Understanding the diagrams:
  • The diagrams illustrate how the RGB colour model works in practice.
  • Each torch emits light at the same intensity.
  • Each torch points towards a different area of the surface.
  • The light in each case is of a single wavelength so produces a spectral colour.
  • The selected wavelengths are: red ...
Light strikes Curved Surface in Line with the Normal

Light strikes Curved Surface in Line with the Normal

This diagram is a new addition to the site! More information will be added ASAP 🙂 ...
Why an Object Appears Transparent in Sunlight

Why an Object Appears Transparent in Sunlight

This is one of a set of 10 diagrams exploring why objects appear to be different colours to an observer.
There are always three key factors that affect the colour of an object.
  • The first is the type of light source and what happens to the light on its journey towards an object.
  • The second is what happens when light strikes different types of objects and materials.
  • The third concerns factors related to the observer which affect what they see and how things appear.
...
RGB Colour Wheel with 196 Colours

RGB Colour Wheel with 196 Colours

This is one of a series of diagrams exploring RGB colour wheels. Colour wheels demonstrate or simulate the effect of colour mixing.
Colour wheels can be used to explore the effect of mixing any type of colour. Light, inks, dyes, artist's paints, pigments and colourants all produce other colours when mixed together. Whilst a colour model outlines a method for mixing and using different types of colour, a colour wheel explores what happens in practice ...
Spectral Colour

Spectral Colour

This diagram is a new addition to the site! More information will be added ASAP 🙂 ...
Mixing RGB Primary Colours

Mixing RGB Primary Colours

This diagram is a new addition to the site! More information will be added ASAP 🙂 ...
RGB Colour Picker: Red to Yellow

RGB Colour Picker: Red to Yellow

This is one of a series of six colour pickers that together show all 1530 fully saturated RGB colours along with their codes. Fully saturated colours are produced by mixing two primary colours together.
Each diagram shows 256 colours starting with a primary and finishing with a secondary colour or visa-vera:
  • Red (primary colour) to yellow (secondary colour)
  • Yellow (secondary) to green (primary)
  • Green (primary) to cyan (secondary)
  • Cyan (secondary) to blue (primary)
  • Blue (primary) to magenta (secondary)
  • Magenta (secondary) to red (primary)
...