james wrote:

In article ,
Benthic wrote:

no absolutley not!!! you will not lose much intensity through the air.

Not through the air, per se, but because light loses its intensity
logrithmically with distance. There are plenty of situations where a
dimmer light, closer up, is more efficient than a brighter light,
further away, because you have to have exponentially brighter light
sources compared to a linear increase in distance.

Maybe it doesn't matter for this application, but it certainly is a
practical problem for photographers.


Intensity at distance d = A (Intensity at distance
0)/(d^2)
where A is a constant