The art and science of colour: Bridging the gap between art and perception

The paper expounds the concept of bridging of the gap between art and science by considering the relation between colour perception and how computational procedures, which mimic our visual system, have been developed to advance digital imaging techniques in science, photography and art. How to describe and measure colour is a problematic activity, for colour scientists, designers and artists alike. Furthermore, there is a difference between how the radiometry of colour is measured and how the appearance of colour is perceived. For contemporary colour science, there is a requirement to accurately measure and specify a colour. However when looking at art, at photographs and at real life situations, attempts to define what we ‘see’ are more complex. Pixels with identical radiances, can appear as radically different colours.1 Although separated by over 100 years, parallels can be drawn between the experiments undertaken by Johann Wolfgang von Goethe in the 18th century, and Edwin Land’s research in the 1950s on colour perception that developed into his theory on Retinex (1964). They can be regarded as examples that bridge the gap between biology, physics and art. Through their very different experiments, Goethe and Land attempted to gain a deeper understanding about the relationship between physical and perceptual colour, and how the brain elaborates the physical signal in order to enhance the extraction of visual information – what appears in our brain and what lies in front of us.2 (Tallis, 2008). Goethe’s interest in human perception as presented in his Farbenlehre (1808)3 attempted to record his many observations on colour phenomena. One of his experiments, using a prism, investigated how fringes of colours appeared and changed according to different black and white patterns; the position of the edges revealed not just spectral colours but also their complementary effect. Edwin Land is better known for his invention of the instant Polaroid film and camera. Moreover, he was interested in the human visual system, how colour is perceived in relation to its context and through his experiments developed the Retinex theory of colour vision (1964). Land and McCann’s Retinex4 starting with analogue electronics and quickly expanding to digital imagery, used a new approach based on computational algorithms that has made it possible and practical to manipulate images based on spatial methods. These algorithms are currently used for image enhancement, to obtain brighter and more colourful photographic images, but can be also be used to emulate and investigate how colour stimuli appears to our visual system.5, 38