Beneath the Surface of Colours

Martti Huttunen

• Publisher: Books on Demand
• Year: 2019
• Print ISBN:
  9789528007319
• Edition: 1
• eBook ISBN:
  9789528055143
• Topic: Biological Sciences
• Subtopic: Ecology
• Index: Biological Sciences

Take a tour beneath the surface of colours!A New Groundbreaking Colour Theory This easy-to-read and versatile book finally explains colour phenomena validly and comprehensively and helps the reader to understand the world of colours surrounding us. The book is also an excellent colour information manual for demanding readers and experts. It presents a new groundbreaking colour theory that indisputably reveals, how the prevailing colour theories are not true.

Interpreting Theories and Understanding Colour Phenomena

The brain is completely indifferent to how the energy of light coming from a visual object is distributed.

The critical analysis of colour phenomena produces a lot of questions, which cannot be answered using current theories.

Why does adding black to yellow turn it green? Why does mixing red and green result in ’dirty brown’ or ‘off-green’ and not neutral grey? Why do yellow glasses brighten the view in daylight, even though they filter off some of the light? Do yellow, red and blue, often held as primary colours, really meet the conditions modern-day science and engineering set for primary colours?

This book interprets theories of vision and, both according and contrary to them, aims to provide some explanations to make the colour phenomena behind these issues more understandable. These explanations are fundamentally linked to such concepts as inverted colour, shadow phenomenon, border contrast, and blueshift.

Colours and Their Mixtures

A systematic presentation of colour phenomena has usually required us to divide colours into at least two systematic groups according to the way they are formed. These are the lightness increasing additive colour system and the lightness reducing subtractive colour system. Sometimes in colour education, colours may also be classified, as Goethe did, to chemical colours (colours as paints), physical colours (colours as lights), and physiological colours (how the eye sees colours). These commonly used divisions may seem clear and easy to learn. Also, their concept of mixing primary colours to form secondary colours feels logical. But are these theories able to answer the important and fundamental question of what colour really is?

All colour-related phenomena, effects, and practical applications have to be explained using some form of colour theory, which in itself always holds an idea of what colour actually is. This explaining also requires that the theory, in some way, defines colour as a phenomenon. When colour education borrows its theories and beliefs, for example, from the world of music, it may lose sight of the actual question and get lost on suspicious sidetracks. Although these sidetracked theories are often protected from open criticism, their weaknesses are easily detectable

Hardly anybody, who is more familiar with colour phenomena, anymore denies that the colours we see are only visual perceptions. If this basic idea is accepted as a starting point, we can justifiably argue that the primary colours of different colour systems exist only in our brain. In addition, when we look at the primary colours of different classification systems and how they are mixed to create secondary colours, we can soon see some interesting phenomena that bring out the inconsistencies of traditional classifications.

Additive Primary Colours

The primary colours of additive colour systems are colours (coloured lights) that cannot be created mixing any other colours (hence the word ‘primary’). When these so-called RGB colours, red, green and blue, are mixed with each other as lights, lightness increases. When same colours are mixed as pigments, lightness doesn’t increase.

The mechanism behind the human colour vision is based on this same additive formation of colour. Our brain interprets all visible colour stimuli, formed with lights or in other ways, as proportional combinations of three different wavelengths (or colours) detected by three different types of cone cells. How this actually happens on a neurological level, is still under debate. Understanding and successfully modelling these mechanisms will create numerous application possibilities to machine vision developers and other researchers.

The principle of human colour vision was utilized when colour display technology was first developed for colour television sets. Computer screen colours are also made visible using only red, green, and blue light as diffused or blurred combinations. This model of human colour vision based on three colours, the so-called was first presented in 1801 by an English polymath and physician Thomas Young (see Young–Helmholtz theory), who can, therefore, be considered as the father of RGB system and colour television. Young argued that the eye doesn’t need a neuron for each and every colour, but that only three types of neurons, each sensitive to its own part of light’s spectrum, is enough for us to have colour vision.

The Subtractive Primary Colours

In the subtractive colour systems, the primary colours are cyan, magenta, and yellow. These are pigments that cannot be mixed from other dyes, and their mixing does not increase the lightness of the resulting colour.

In subtractive colour formation, colours are created mixing together opaque pigments. Depending on the binders and solvents used, these colours are either averages of or darker than the original pigments. For example, when yellow and cyan dye powder are mixed together (without solvents and binders), we will see green with a lightness value that is the average of the lightness values of its yellow and cyan component powders.

In contrast, when translucent colour gels are used, the resulting colours are darker than the original colours, because more of the brightness is filtered off than when pigments are mixed together (see Colour Glossary: Absorption). This lightness-reducing CMYK colour formation is used, for example, in colour photography and in offset printing. In CMYK images, the fourth ‘colour’ is actually the hueless black pigment (K = Black), which is used to increase luminance differences in the image. When the light source is behind coloured gels, this sort of additional contrast increasing becomes unnecessary.

A CMY colour image needs black (K) to increase lightness differences and darkness (= CMYK).

Lightness decreases when coloured gels are stacked on top of one another.

When dye powders are mixed, the lightness level of the resulting colour is an average of the lightness levels of the used powders.

Optical Colour Formation

Optical (diffuse, fuzzy) colour refers to colours that are formed from multiple colours that are optically undifferentiated, simultaneous stimuli. This means that the information coming from the retina is interpreted in the brain as a single colour. This happens, for example, when we look at a rasterized colour image, a TV screen, or a fabric made of warp and weft yarns of different colours. Similarly, if a spinning top has coloured sectors, they will appear as a uniform colour, when the eye is unable to distinguish between separate sectors of a fast-rotating top.

The brain receives visual information coming from the retinal cells through the red, green and blue ‘colour channels’ as monochrome images. It’s only in the visual cortex that these separate visual stimuli with differing lightness levels are combined to form a sensation of colour. Since the image projected onto the retina is always analysed in the brain as stimuli from separate RGB channels, we can well say that a colour sensation is ’fuzzy’ even when we look at, for example, a surface painted only with one colour

The Pointillist’s Problem: How to Interpret the Theory

The French painter Georges Seurat (1859–1891) was inspired by colour theories of his time and by the additive colour formation. He believed that the small coloured specks painted onto a canvas could, when optically combined, produce bright and luminous colour sensations. This painting technique, based on optical mixing of colours, is called Neo-Impressionism or Pointillism.

The deliberate collision of science and art in the additive and subtractive colour formation didn`t produce, against all expectations, scientific art, but a short-lived technique of painting small dots called Pointillism.

The ‘scientific’ base of the Pointillist colour formation, nevertheless, had a problem that the artists didn’t fully understand and weren’t able to solve. They assumed that dots of pigment would mix like lights and form bright colours. When this didn’t happen, they thought that sufficiently clean and colourful pigments just weren’t available.

In theory, the Pointillists’ idea of mixing colours was exactly right. When the additive primary colours are mixed optically, the result will be a diffuse mixture of lightness values of the original colours, a so-called secondary colour, such as yellow, magenta or cyan. But when a painter used...

Table of contents

• Table of Contents
• For the Reader
• Why ’Beneath the Surface’
• What is Colour?
• Words in Front and Behind Colours
• Colour Perception
• Levels of Effect and Meaning in Colour From Universal to Particular
• Colour Research: A Multidisciplinary Science
• Interpreting Theories and Understanding Colour Phenomena
• There is No Colour Illusion
• Aesthetics of Showing and Concealing
• History of Colour
• Interior Colours
• Colours and Cultural Landscape
• Colours in Communication
• Colours of Animal Kingdom
• Inverted Colour Theory
• Colour Glossary
• Further Reading
• Attachments
• Copyright