The accent lighting of three-dimensional shapes and surface textures using directed light from a point light source. It is generally expressed through the improvement in shadow quality.
Directed light from the front produces a strong modelling ability. Light from above causes the object to cast strong shadows on itself. Light from behind creates a silhouette. The steeper the incident light, the more pronounced the shadow effect.
A single accent light produces a strong shadow on an object. Harsh contrasts between light and dark areas can be reduced by combining light from different directions. A strong accent light from one side creates a dominant viewing direction. Complementing the primary frontal light with back-lighting can reveal textures on the rear of the object. Diffuse light from above results in the object appearing less three-dimensional than if illuminated with directed accent light.
Accent light enhances the three-dimensionality of objects. The use of several spotlights reduces the light-dark contrasts on the object, which can make textures more apparent. Lighting of equal power from different sides reduces the three-dimensional effect. The differentiation of illuminance levels with key light, supplemented with a lower intensity fill light and a little back light produces a balanced effect. This lighting concept gives objects a three-dimensional appearance and ensures that areas in shadow can still be appreciated. Important areas are ideally emphasised with key light. Where objects are viewed from all sides, back light on the rear of the object allows the texture to be perceived effectively. Diffuse light - e.g. from a luminous ceiling - can also reduce the harsh contrasts between light and dark areas caused by an accent light and results in objects appearing softer. Lighting solely with undirected, diffuse light will give hardly any shadows and produce a poorly sculptured effect.
The steeper the incident light, the more pronounced the shadow effect. Objects can be illuminated well when the direction of light is between 5° and 45° to the vertical. The optimal direction of light for illuminating objects is at 30°. This avoids strong reflected glare or undesirable shadows on people or objects.
Pinacoteca Vaticana, Rome
Guggenheim Museum, Bilbao
Hermitage, St. Petersburg
Hermitage, St. Petersburg
Combining light from different directions
The key light is aimed at the object from the front, offset to one side. The fill light is also incident from the front but from the opposite side. The back light illuminates the object from behind. The optimum angle of inclination off the vertical for objects is at around 30°. In this way strong reflections, glare and undesirable shadows on people or other objects are avoided.
Picasso Museum, Barcelona
Museum Ara Pacis, Rome
Museum IVAM, Valencia
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