CCD and Astrometric Eyepiece Measurements of WDS 19121+4951

Abstract

There are two methods often used to observe and measure the separation of known binary stars. One uses an astrometric eyepiece and the other uses CCD images. With measurements taken at the Colorado Mountain College Ball Observatory, the relative accuracy and precision of these two methods was compared using observations of the known binary WDS 19121+4951. The use of CCD Images was more accurate and precise than the use of an astrometric eyepiece. The average position angle and separation measured using the astrometric eyepiece were 200.6⁰ and 8.0" with a standard deviation of 2.29 and 0.51 respectively, and are considerably far from the published orbital predictions, whereas the average position angle and separation measured using CCD Images were 202.89⁰ and 7.02" with a standard deviation of 0.11 and 0.016 which is much closer to the published orbital predictions.