Light source-for proper development, the plants need not only the right amount of light, but above all the proper spectrum of light. Different types of lamps and light sources are used, which emit different amounts of light. The light effect, that is, the ability of a light source to convert Watts to lumens is given in lumens on Wat. It is an important indicator of light source performance. While the amount of lumens remains the same, the illumination decreases. On the same surface area falls a smaller light flux.