The article is devoted to determining the adaptation level of the visual system to illumination in condition of changing the surrounding field brightness arising from the dynamic control of artificial lighting in industrial premises, as well as when controlling the brightness of modern displays’ illumination. There is given a general idea of the visual system structure and retina properties and considered two consecutive mechanisms of adaptation to illumination. In the article an experimental calculation of determining the contrast threshold under conditions of complete adaptation is presented, the results of which allow us to conclude that there is no dependence of the color tone perception on brightness in a wide range of its measurements. The research materials can be used to create lighting control systems and select appropriate displays for operators of automated control systems in order to minimize the load on the organs of vision.