You are now visiting our Global professional lighting website, visit your local website by going to the USA website

More brands from

Lighting in


How to measure illuminance




Why measure1

Ideal measuring conditions


  • Measure without contribution of daylight.
  • Determine the height and position of the measurement.
  • Be sure your body does not form an obstacle for the photocell.
  • It will hold the light captured by the cell.

Measuring spaces


  • You have to measure a set of points using a grid. The smaller the space - the smaller the distance between measure points.
  • Measuring one or two points gives you just a rough indication about the light level.
  • For the rough indication follow the key areas described in each of the application areas.
Why measure2

Measuring horizontally and vertically


  • Measure the horizontal (Eh) or vertical light level (Ev).
  • Make sure the photocell is placed parallel to the surface
Why measure 5 plan



Previous      Next



November 16

Zen and the Art of Lighting Design

Presented by Peter A. Hugh


November 20

Smart Street Lighting Leadership

Presented by Eric Woods and Barbara Kreissler


December 6

Light in Space

Presented by Maarten Jamin, Vesna Petresin, Gernot Oberfell


January 17

Light Pollution - The Effects on Animals and Humans

Presented by Kamiel Spoelstra, Steven Lockley


February 20

A Fine Dining Experience (The Art of Consulting as a Lighting Designer)

Presented by Dr. Emrah Baki Ulas


March 21

Fundamental and Inspirational Light

Presented by Enrique Garcia-Carrera

Paul Traynor
Paul Traynor
Marlyn Zelkowitz

We're talking about