# New Person here. Luminance Flux?



## Bertn (Apr 6, 2012)

I am thoroughly confused about the meaning of Luminance Flux. I am more familiar with foot lamperts the light diffused through a medium and measured. For example, a projector shining light onto a screen and measured from the viewing side. Is Luminance Flux similar to a foot candle measurement? I think about a foot candle measurement as being a measurement of light shining onto a surface is Luminance Flux a similar type measurement? 

The reason I have asked these questions is because all of the high output LED's quote their light output in Luminance Flux.


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## StarHalo (Apr 6, 2012)

Luminous flux is the total amount of light being emitted that you can see, measured in lumens. A candle flame is 13 lumens, a car headlight is ~500 lumens, a 60 watt lightbulb is ~800 lumens.

Bear in mind that this measurement does not in any way take into account how that light is directed; your average Mini-Maglite with worn batteries is only ~13 lumens like the candle flame, yet because it is all concentrated in one direction, it makes a useful flashlight.


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## Bertn (Apr 7, 2012)

Thanks! The examples you gave are a big help. I guess it makes sense that the measurement doesn't have anything to do with how the light is directed. 800 lumens output from a light bulb doens't look very bright but if you were to focus the light it would appear much brighter.


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