Education + Resources, Lighting Design

How to Evaluate Light Sources

Electrical Contractor recently published an article I wrote about a simple methodology for evaluating light sources based on a basic series of questions:

• What is the distribution of the light? Distribution is measured in candelas (cd).
• How long does the lamp last? Service life is measured in hours.
• How much light does it produce? Light output is measured in lumens (Lm).
• How much electric power does the system require? Power is measured in watts (W).
• How efficient is it compared to others? Efficacy is measured in lumens per watt (LPW).
• What is the color appearance of the source? Color tone is measured in kelvins (K).
• How well does the source render colors? Color rendering is expressed on the color rendering index (CRI).

Check it out here.

Image courtesy of Peter Ngai.

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Craig DiLouie


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