An attempt to quantify seeing through disturbed atmospheric ground layers

This paper relates to atmospheric seeing in daylight over a horizontal range of 775 m. The target was an illuminated circular sector pattern with which an observer may obtain optical contrast functions by stepwise quantitative estimations. Such functions were composed by marking the visual limits of recognition for each sector of the target during various weather situations. Characteristic features of the results of this work are summarized in the legends of the figures.