Astrometric distortion calibration of a portable refractor

摘要

A compact refractor simplifies imaging stars during a total solar eclipse from remote, temporary locations. To achieve astrometric accuracy, cubic distortion terms were measured using hundreds of nighttime images. A detailed procedure is presented here, along with an example from a portable telescope. The results show that precisions down to the 20 mas level are possible with commercial equipment. (C) 2017 Optical Society of America