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brightness enhancement

[5.2.6] (Also known as Bartley effect enhancement)

If a light of relatively high brightness is first seen as a steady light and is then repetitively extinguished about 4 to 10 times per second, its apparent brilliance increases, rather than diminishes, by a factor of up to 5. Its conspicuity increases considerably, even though the power consumption and the photometric quantity of light may be half or less.The same effect may occur at lower levels of luminance if the light is seen extra-foveally.

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