Fig. 3

Separation between pairs of stars in the NGC 6388 data set plotted against frame number before any distortion correction. The left panel shows the separation in the x-direction, the middle panel in the y-direction, and the right panel the full separation . The left y-axes are given in pixels while the right ones give the measured distances in seconds of arc. The small straight lines mark the frames after which a new five point sequence of jitter movements was started. The x-axes can also be seen as a time sequence as the individual frames were obtained subsequently, the first ten with an exposure time of 240 s and the last 20 with an exposure time of 120 s.
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.