Basic Functions of LightingLocal or task illumination: See recommendations in IES tables; consider placement of light sources and reflectance values of surrounding surfaces

Task lighting

Basic Functions of Lighting

General or ambient illumination: Provides fill lighting to reduce brightness contrasts. Common techniques used:

Downlighting: Used for desk or table top tasks or for ambient lighting in spaces with high ceilings; light distributed through interreflection from walls

Uplighting: Good ambient lighting technique or accent for interesting surfaces that are up; important that surfaces have high value, matte finish to reflect light

Uplighting

Basic Functions of Lighting, cont.

Accent lighting: Used to illuminate architectural or interior elements. Common techniques include:

Grazing: Used to emphasize textural qualities of vertical surfaces and to define a space by featuring one wall over another. Achieved by directing light parallel to featured surface, appx 6-12 from surface

Grazing

Grazing

Wallwashing: Unifies a wall with sheet of uniform brightness. Wallwashing also flattens texture of vertical surface; provides soft, ambient reflected light; attracts attention to wall; and unifies diverse objects on wall.

Good example of wall washing on right wall. Poor examples

Backlighting: Rear lighting technique that diffuses light through translucent materials.

Backlighting

Highlighting: Emphasizes featured object by creating 5 to 10 times the amount of brightness on the object than in the background. High contrast attracts attention.

Highlighting

Silhouetting: Sandwiches an object between viewer and sheet of light. Object is outlined by the light the brightness of which serves as negative space. Details on face of object are obliterated.

Silhouetting

Basic Functions of Lighting, cont.

Decorative Lighting1.Light as art: Light output assumes unique and original forms. High contrast environment enhances impact.

Shadowplay: Occurs where pattern of light is the background, or negative space, and shape of shadow carries the message.

Shadowplay

Beamplay: Opposite of shadowplay where light beam becomes the visual feature. Sometimes achieved with gobos

Beamplay

Sparkle: Occurs when bits of small brightness appear on a dark background. Requires very high contrast to be effective.

Sparkle

Sparkle

Colored light: Use of colored light sources to create special visual effects

Colored light

Basic Functions of Lighting2. Decorative Luminaires: Often used for style or glitter/sparkle rather than light-producing qualities. To reduce contrast if strictly decorative, use low wattage lamps, dimming switch, and supplementary ambient & task lighting