The exterior lighting scheme, by Roger Narboni of Concepto Agency, adds a touch of magic to an already spectacular piece of architecture as the balance of light and shadow gives a form of beauty which is not seen during the day.

The west front of the coronation cathedral of France is an elegant design of great unity. The challenge of lighting such a building lies in its sheer volume – there are 2,203 statues alone. The lighting had to realize the division of the façade, which features all the essential French Gothic elements- triple doorway, arcade and rose window, line of kings and twin towers - without overlighting, yet still give special emphasis to focal points.

The effect was achieved by the use of a carefully thought out design strategy and illuminance hierarchy. The light gradually intensifies upwards in succeeding stages, from 5 lux for the buttressed doorways to 40 lux at the towers, so that the eye moves easily and smoothly upwards. Only major details were highlighted, to 200-300 lux. The result is a sensitive scheme which has unity, beauty and economy.

The project has used 150 circular symmetrical Contrast floodlights, of which 60 were small 35W ‘pinspot’ units. These were augmented by 1,114 recessed end-glow fibre optic terminals, chosen to light details and statues. The fibre optics are controlled by 110 light generators via three to 20 metre long glass tails.

Metal halide was the selected light source (warm 3000K and cool 4200K for the floodlights and fibre optics respectively) to illuminate the façade in crisp white light to contrast with the golden yellow of the surrounding street lighting.

The majority of light points have been close-mounted and aimed upwards which reverses the shadows and gives a fresh appeal to the night time appearance of the building. The form of the shadows is controlled by varying the closeness and beam angle of the lighting, the fibre optics being adjustable from 7-36 degrees. This mixture of light and dark areas adds realism to the sumptuous array of carvings, as well as strengthening the three-dimensional impact of the cathedral in the visual scene.