Lighting • Basics

Without light nothing runs for us as audiovision professionals. We need light for figurative representation. We use light for the taking pictures and we use the light for the presentation of the images/pictures as well as for any other kind of visual representation.

For humans, the light is the visible range of the electromagnetic radiation. This extends from approximately 380 to 780 nanometers (nm) wavelength. That corresponds to a frequency from approximately 789 to 386THz. An accurate border cannot be specified, since the sensitivity of the human eye decreases gradually in the frontier.

The physiology of the color effect is based on the different spectral sensitivity of the pigments of a specific small area in the eye. The different noticed colors correspond to different wavelengthot the light.

Physics means that light (amongst others) possesses specific wave characteristics. The main source of the light on earth is our sun. Artificial sources of light are for example bulbs, fluorescent tubes, light emitting diodes (LED), lasers and chemical light.

Sizes and units

In our daily work we have to consider a few important factors about the light:

• The speed of light is 299'792.458 km/second;
• The light-measurement is lumen;
• The quantity of light in lumen per second;
• Luminous intensity is candela;
• The brilliance in candela/m²;
• The density of light in lux and
• The color temperature in °Kelvin.

Light and the law

Light is an important environmental factor and thereby belongs to immissions. Light immisionen from lighting systems can disturb the living comfort of humans and animals. Particularly disturbing is intensively colored or flashing light. To strong light • in particular laser beams • can be harmful and cause eye injuries.