Scripps Institution of Oceanography

SIO Reference 58-35. It is shown that the probability of receiving light from an object viewed through a turbulent atmosphere follows a normal Gaussian distribution. Furthermore the root mean square angular deflection of the points of any object \dll be proportional to the square root of the object-to-observer distance.From relations of the type described in the examples, it is possible to predict the apparent contrast throughout a given scene, provided the inherent contrast distribution, the Optical Air State, and the range of the target is known. The Optical Air State for a given condition of atmosphere can be measured using a telephotometer and a series of long thin black bars of varying widths.