Evaluation and Control of Brightness Levels for Television Studio Lighting

One of the best known units of measurement in the practice of applied lighting is the foot-candle. It is used to measure incident lighting density and corresponds to a uniformly distributed light flux of one lumen per square foot. However, we are usually concerned with incident light only as a means of obtaining surface reflections and the foot-Lambert then becomes an important unit of measurement, since it represents the apparent foot-candle, or the value of incident light in foot-candles multiplied by the reflectance factor of the diffusely reflecting surface. — It is shown that knowledge of foot-candle data alone does not necessarily lead to an accurate calculation of foot-Lambert values where colored surfaces are concerned. Color is discussed from the standpoint of spectral distribution in the illuminant and its effect upon brightness reflectance of colored surfaces. It is also shown that apparent brightness values as seen by the eye do not correspond to the actual values.

Print ISSN

0361-4573

Published

1960-07

Content type

Original Research

DOI

10.5594/J15587