Humans need light to perceive objects. The human eye also has a built-in peculiarity: adaptivity.<\/p>\n\n
Sensitivity to light in the eye is adjusted according to light conditions. If you move from a well-lit room to a room with little light, you will initially perceive little to nothing. After a short time, the eye adapts to the light conditions and manages to perceive objects again, this can take up to 2 minutes. Conversely, from dark to light, it only takes a few seconds to regain good vision. Very little light is needed to observe movement and shape. Experiencing color, nuances and details requires a lot of light.<\/p>\n\n
The level of lighting required in rooms depends on a number of factors:
The luminance (the amount of light, which is reflected by a surface) of an object depends on the illuminance (the amount of light that falls on it) and on the extent to which the object reflects back the received light, i.e., on the reflectance factor of the object.<\/p>\n\n
When the object has a low reflectance factor and one cannot switch to light-colored material, one is forced to apply high illuminance to achieve a high luminance of the object.<\/p>\n\n
The design of light, lighting and lighting installations requires knowledge regarding specific quantities, units, optical properties of matter, ergonomic and biological properties of the eye and man, electrical engineering, lighting technology and skill to integrate all these components into an appropriate lighting recommendation.<\/p>\n\n
Practice has shown that good lighting advice is based on a good interpretation of the client’s requirements and wishes and the lighting designer’s sense and interpretation of the architectural and interior technical design principles. In addition, lighting advice must comply with current laws and regulations regarding the environment and energy, as well as working conditions and comfort or the prevention of nuisance and discomfort for users.<\/p>\n\n