The Photometric Connection - Part 1

Factors in, and the quantitative uncertainties of, luminaires and photometry, lighting calculations and field measurements are examined.

Three broad categories contribute to the potential differences between predicted and observed luminous values: luminaires and photometry, lighting calculations, and field measurements. Individual factors in the three categories will be reviewed, and the quantitative uncertainties of these factors will be discussed. To limit the scope, principal emphasis will be on factors related to illuminance, but an extension to other metrics is obvious. The objective will be to show the large number of factors with affect the correlation between prediction and measurement.