Light colour, which is the colour temperature, is measured in Kelvins [K].
The lower the Kelvin number is, the warmer is the light colour – closer to yellow (e.g. a candle light, a sunset), the higher the number is, the cooler is the light – becoming more and more blue (e.g. daylight, sunrise or a lightning).
Selection of light depends on the place and activity that should be lighted as the light colour influences our frame of mind and ability to focus very much.
A human relaxes best at warm light – approx. 2700 K. It gives the impression of cosiness and helps to relax. The warm light sources are worth using at homes, in cafés, tea rooms and restaurants.
The daylight, approx. 3000 K, is the most neutral which makes it suitable for all common activities and daily functioning. It is plant-friendly as it imitates their natural environment. Selection of this light colour temperature is the safest as the colour is all-purpose and has no great influence on our mood.
The cold colour have a stimulating effect on a human which favours his or her increased activity and concentration. Thus, it is ideal for office work, studying, as well as for using in sport facilities.
The light selection depends also on the colours of objects or places to be lit. For cold colours (grey, blue, silver) cold light matches best. For warm colours (yellow, orange, red, gold), better use warm light. This way the colours will be exposed best and unnecessary dissonance avoided.