The Psychology of Visual Art Eye, Brain and Art

Introduction

This chapter concentrates on how the eye works and how this function impacts on art. To set the scene, it will be useful to know a little about the physical properties of the stimulus for vision, light. The precise physical nature of light has perplexed philosophers and scientists for centuries and is not yet completely understood. Light is a form of energy known as electromagnetic energy because it has both electrical and magnetic properties and it is carried in small packets called photons. The electromagnetic field of each photon has a characteristic vibration frequency that can vary from a few thousand vibration cycles per second to many billions of cycles per second. The standard way of measuring vibration frequency is in terms of the distance between adjacent peaks in the vibrating wave, known as its wavelength. Across the full electromagnetic spectrum, wavelength can vary from extremely short wavelengths that are a fraction of the size of atoms (X-rays and gamma rays, the very highest frequencies) to very long wavelengths that can be many kilometres long (the lowest frequencies). The energy that you can see as light spans only a tiny proportion of the electromagnetic spectrum, corresponding to wavelengths between 400 nm and 700 nm (billionths of a metre). Light wavelength is associated with colour experiences, with the longer wavelengths appearing red or orange and the shorter wavelengths appearing blue or violet. Yellow and green sensations are evoked by middle wavelengths. Electromagnetic energy in the visible band-light is well behaved in the sense that it reflects off most surfaces and can be focused by lenses. As the sense organ for vision, the eye takes advantage of this good behaviour.