The inverse square law (ISL) is one of those principles of photography that drives people crazy. It’s a fairly simply concept that’s broken down into a rather confusing sentence. It states that the intensity of an effect such as illumination or gravitational force changes in inverse proportion to the square of the distance from the source. That, to most people means absolutely nothing.
So, in this video, photographer Joe Edelman is here to explain it in straightforward terms. In his usual way, Joe has lots of diagrams and practical examples to illustrate what it’s all about. The ISL can be a difficult one to wrap your head around at first. Once you understand it, though, it all makes complete sense. You’ll wonder how you ever got on without knowing it.