Page 189 - The Power of Light, Colour and Sound for Health and Wellness draft

attain 100 while fuorescent tubes often only measure 70 and orange low pressure sodium lamps have zero value.
Emotions of light
Intensely coloured beams of light are supremely powerful in creating visual and emotional atmospheres. The expressive qualities of artistic lighting can transform an ordinary room into a multitude of visual spaces. The dominant emotional dimension is usually the dramatic thermal contrast between warm and cold – but light can also accentuate impressions of openness or privacy, grandeur or quietude. Practical applications include homes and schools, offces and factories, hospitals and prisons. The affective modalities are without end and the lighting designer virtually becomes a consulting psychotherapist. The grand masters of emotional lighting are found at opera houses and rock concerts conducting luminous dramas over the whole spectrum of human sentiments.
Plasticity of light
Humans are originally outdoor animals who comparatively recently started to live indoors. An organic lighting scheme should try to imitate the cyclical changes of natural daylight with its rich supply of temporal clues. Sun and sky with wandering clouds vary throughout the daytime. A modestly realistic simulation is dimmable light and adaptable luminaries adjustable according to individual need. Personal light appetites are quite diverse and must be thoroughly respected. Worst of all are the uniformly glaring ceilings as seen in offces where spatial or temporal information is completely lost.
Absence of light
Contemporary urban dwellers have never experienced the full depth of darkness and stellar constellations are unknown among young children. There is always the glare of a streetlamp or a mobile phone in standby mode. The body clock needs obscurity to stabilize its chronobiological rhythms and the visual pigments inside every rod and cone require darkness to regenerate their molecular structure.
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