Lumens and watts are often confused: wattage is how much electricity the light uses, not the light emitted from the bulb. Make sure that the measurement you are looking for is lumen and not wattage.
A lumen quantifies how much light is emitted by a source (for example, a light bulb) and is an SI (metric) unit of light power. Candle power (commonly called candela) measures the brightness of the light at the source and is an SI measurement of how much light falls a certain distance from the source. Candle power and lumens measure two different things, therefore it's impossible to accurately convert between the two. However, you can get a good approximation with the following candle power to lumens formula: L=C/0.07958, where L is lumens and C is candle power.
Determine the candlepower of your light source. A light meter can be used to measure candlepower.
Insert the candlepower measurement into the following formula: L=C/0.07958, For example, 200 candlepower would equal: L = 200 candlepower / 0.07958.
Do the division using a calculator: 200 candlepower / 0.07958 = 2 513 lumens.
About the Author
Stephanie Ellen teaches mathematics and statistics at the university and college level. She coauthored a statistics textbook published by Houghton-Mifflin. She has been writing professionally since 2008. Ellen holds a Bachelor of Science in health science from State University New York, a master's degree in math education from Jacksonville University and a Master of Arts in creative writing from National University.
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