Quality of the Lighting Environment
What is good lighting?
Basically, the lighting in a particular instance can be described as good when it creates a luminous environment that strikes the right balance between the needs of visual performance on the one hand and the needs of visual satisfaction on the other.
The visual environment embraces furniture, ceiling and walls, building materials like brick and timber, components like windows and doors and all parts of the landscape outdoors – in short, all the things that together constitute our surroundings.
Visual performance and visual satisfaction
Lighting makes it possible to determine our visual perception of realities. It provides us with a means of quantifying parameters like illuminance, luminance and glare that are important for visual performance. At the same time, it also allows us to control things like ambience, color appearance, color rendering, brightness composition, contrast and character of the materials used. The weighting of these last-mentioned factors cannot be done objectively as they are an expression of human judgement yet together they determine the degree of visual satisfaction created by lighting.
Good lighting contributes to the quality of life and increases comfort and efficiency with which work functions are performed. The difference in cost between such lighting and that which can be described as just adequate is relatively small, and is in any case offset by the benefits achieved.
But good lighting, whether as part of a new project or part of a renovation scheme, cannot be left to chance, It must be planned from the outset by experts: only then will it be truly cost and energy effective.