Colour Theory Lecture 1

COP Lecture: Colour Theory

Systematic Colour (part 1)- An Introduction to Colour Theory

• colour is dependent on what is around it
• isolated colour is always surrounded by other things that will change how we interpret that colour
• it is changeable
• three areas: physical, physiological and phycological
• physical: 
• spectral colour is a colour that is evoked by a single wavelength of light within a visible spectrum
• a single wavelength, or narrow band of wavelengths generates monochromatic light
• every wavelength of light is perceived as a spectral colour in a continuous spectrum
• the colours of similar or sufficiently close wavelengths are often indistinguishable by the human eye
• colour is based on the principles of light
• light is white, and all light is made up of all the colours we can possibly see, the only way we can see them is when they hit our eyes and refract
• our perception of any colour is based on the eye receiving light that has been reflected from a surface or an object, it could be part of our eye but more commonly is objects around us
• even when we have a base colour, because we perceive colour throughout reflected light, the amount of light, the colour of the surface itself and how absorbent the base colour is can all affect what we perceive 
• the eye contains two kinds of receptors:
• Rods- convey shades of black, white and grey
• Cones- allow the brain to perceive colour
• There are 3 types of cones: 
• Type 1: is sensitive to red and orange light
• Type 2: sensitive to green light
• Type 3- sensitive to blue
• When a single cone is stimulated the brain receives the corresponding colour
• if both our green and red orange cones are stimulated we see yellow 
• due to physiological response, the ye can be fooled into seeing the full range of colours

Systematic colour:

• LOOK AT TERMS ON PRESENTATION
• Josef Albers and Johannes Itten - the art of colour
• colour design workbook- library
• colour - pigment- media: 
• primaries: red blue and yellow
• primaries can be mixed to make secondaries 
• primaries can be mixed to make tersharies 
• complimentary colours- the chromatic opposite of one colour 
• mixing complimentary colours makes merky greys (e.g they cancel out each others wavelengths and neutralise) THESE ARE CALLED NEUTRALS
• primary colours cant be made by mixing any other colours

Spectral Colour:

• the eye cannot differentiate between spectral yellow and some combination of red and green
• the same accounts for our perception of cyan, magenta 
• COLOUR MODES: 
• 1 colour mode is RGB: this one relates to light where primaries are red green and blue and can been seen on photoshop, TV on screen etc
• 2nd colour mode is CMYK: this one is cyan, magenta, yellow and black and is used for printed work, relates to pigment
• subtractive colour: (YMC- ink) by mixing all colours together you get a pure black or an absence of colour
• additive colour: (RGB- light) if you mix all colours together you end up with white or white light 

Dimensions of Colour:

• chromatic value= hue, tone and saturation 
• hue: the colour itself, the response we have to it, the way we describe how we recognise the colour 
• luminance or tonal values: how vivid is it, how much light does it reflect, the varying shades of a colour made by making them duller or lighter
• adding more light to something creates a tint
• saturation is how much of a colour we can see, and how vivid it is, can also be desaturated, can also be affected by moving through a hue, shade or tint

- Colour is contextual