Coloured Light as a Tool for Working with Architectural Form in the Night Environment of the City

For the past decades the light environment of the evening city has become a critical component of the architectural and administrative activities. Today, the lighting systems not only allow making an object or an entire street ‘visible’ in the evening, but also provide for the development of their new architectural image. The opportunities offered by the white artificial light were appreciated to work with the illuminated polychrome objects long ago. The white light with various spectral properties is capable sometimes to influence dramatically the perception of the architectural form, as with its high intensity under the darkness adaptation conditions it has the capability to ‘absorb’ (turn off) the ‘object’ colour of the illuminated facade surface. In particular, the specifics creates an ‘evening’ object image different from the daily one, where the colour scheme used in the material object is often not critical. In contrast, the chromatic light under certain conditions allows not only maintaining the colouristic nature of the environment existing under the natural lighting conditions, but also developing and unifying it in a unique manner, creating a new colour palette. The description of the main areas of the evening environment arrangement with the chromatic light is provided. A significant work experience has been already accumulated in this field by the light design experts. The colour light opportunities and, even more so, the technologies of dealing with it have not been appreciated and adopted by architects to the full extent yet. The article considers the application specifics of the colour light as a fully functional instrument for dealing with the object form under the night urban conditions. The results of an experiment to study the interaction between the colour of material objects and the colour light based on the analysis of Moscow polychrome, which was carried out in the laboratory of the Moscow Architectural Institute (State Academy), are presented. Visual observations enabled to determine the impact of light with the colour light filters selected for the experiment on the colour samples typical for a number of historical periods in the Moscow architecture. The colour samples typical for the facades of buildings erected in a number of historical periods in the capital architecture were illuminated in the darkness with the light of slide projectors with IL and R, G, B glass light filters, and changes in their visual perception were assessed using the NCS atlas, then the identified colour shifts were determined with the use of E. Rabkin’s atlas by three parameters (λ, P, L). A hypothesis was expressed about the possible use of the results of such studies not only in the architectural colour lighting of the modern urban environment, but also in such a new application area as restoration, preservation and interactive integration of the historical and architectural heritage sites into the programmable image-bearing environment.