Behind the Lens

4.12Inverse Square Dancing: A Practical Look at the Inverse Square Law

When the venerable Bill Klages last left the pages of TV Technology, he was discussing some mathematical esoterica regarding the inverse square law and I was a bit inspired to pick up, somewhat, from where he left off.

We all know inverse square law as the rule of physics regarding point sources where the intensity of the source will diminish by the square of the distance traveled. For most lighting professionals, this is a rule to determine falloff of a fixture at a specific distance. This works two ways, if you have a fixed relationship between your fixture and your subject, then using inverse square can aid in determining the size of fixture necessary to light your subject ...