Lux & throw relationship?

[kosPap]

hi all! I was wondring is there an easy mathematical relationship between lux and throw?

Can I apply the inverse square law when i combine hotspot maesuremetns in order to deduct throw?


i.e. one flashlight meausers 900 lux and another 3600....can I assume that the secong will have double the throw of the first?

thanks, kostas

 

[Saint_Dogbert]

No, because a single throw value tells you nothing about beam divergence. You'd need at least two measurements at different distances from each flashlight to get an idea of throw.

 

[HKJ]

hi all! I was wondring is there an easy mathematical relationship between lux and throw?

Can I apply the inverse square law when i combine hotspot maesuremetns in order to deduct throw?


i.e. one flashlight meausers 900 lux and another 3600....can I assume that the secong will have double the throw of the first?

thanks, kostas

That depends on how the lux is measured, if it is measured at some distance (like 5 meters) you can do it, but measurements at one meter is not good enough for it.

But the throw value is a very limited specification, the distribution of the light also has a very big significance.

 

[Ragiska]

yes, see ANSI/NEMA FL 1 section 2.2.6