More Lighting Talk

[reefburnaby]

Hi,

That basically sums up why I like Iwasakis.

But, the problem is that if the distance between the lamp and coral double, the PAR is reduce by 1/4 its value. Let's say the average distance between a lamp and a coral is 18inches (or triple the distance), then the PAR would be reduced by 1/9 (square of the distance) of 2000 or approx 200 uE/m^2-s.

Oceans do suffer from the same problem, so 18 inches in to the ocean does not result in adrastric drop in PAR -- the distance between the sun and the surface of the ocean is several billion times larger than 18 inches. In order to reduce normal sunlight's PAR by 1/4, we would need to double the distance between the sun and the ocean -- which would be very far away.

So, although we measure 2000uE/s-m^2 on the surface of the water in our reefs and in the ocean, the PAR is drastically different between our reefs and the ocean near 0.1 to 40 meters under the surface.

Hope that helps.

- Victor.

[ 05 January 2002: Message edited by: reefburnaby ]