Knowledge base

Amount of light (luminous energy, Q)

Luminous quantity (Q) is a measure of the total light emitted from a light source over a given period. It is the total amount of light emitted or received by...

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Obie light (eye light)

Obie lighting refers to a technique used in film and video production to create a light reflection in an actor's eyes , enhancing the vibrancy and depth of the face....

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One-K lamp

One-K is a term often used in theatrical and film lighting , and refers to a specific type of bulb with an output of 1,000 watts . The term comes...

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Nit (nt)

The nit (abbreviated nt) is a unit of luminance , which describes the amount of light per unit area. It is equal to 1 candela per square meter (cd/m²) and...

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Lighting Effectiveness Factor (LEF)

The Lighting Effectiveness Factor (LEF) is a measure of the efficiency and effectiveness of a lighting system , taking into account the amount of light actually used for the intended...

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Lighting Cooling Index (LCI)

The Lighting Cooling Index (LCI) is a measure of the coolness of a light source. This index helps determine the color temperature of light sources, which is essential for creating...

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Luminaire Dirt Depreciation (LDD)

Luminaire Dirt Depreciation (LDD) is a factor that takes into account the decrease in light output due to dirt, dust and the build-up of contaminants in or on a luminaire....

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Light Loss Factor (LLF)

The Light Loss Factor (LLF) is a correction factor that accounts for the loss of light output over the life of a lighting system . This loss can be caused...

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Maximum Overall Length (MOL)

The Maximum Overall Length (MOL) is the total length of a lamp , measured from the very tip of the lamp (e.g. the top of the glass bulb) to the...

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Light Center Length (LCL)

The Light Center Length (LCL) is the distance from the center of the light source to the base of the lamp . This is measured in millimeters (mm) and is...

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Klieg lamp

A Klieg lamp is a powerful carbon arc lamp originally used in the film industry for lighting during filming. The lamp is named after the brothers John and Anton Kliegl...

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Koschmieder's law

Koschmieder's law describes the relationship between visibility and the atmospheric extinction coefficient. This law states that visibility is inversely proportional to the extinction coefficient of the air. In other words,...

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