Accuracy of angular measurement with various targets at different distances

Five commonly used survey targets were tested for angular measurement accuracy using various target-distance-theodolite combinations. The results show that for distances less than 300 m, the geodetic target, the steel nail, and the plumb bob string perform fairly equally. For distances more than that, all targets tend to converge to a common accuracy value. The results of this experiment are relevant to surveyors, civil engineers, and other field measuring scientists who are interested in creating and applying land or geographic information systems (LIS/GIS) that use cheap and simple mensuration equipment to collect survey data