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Table 1

Observations log and night conditions.

Night FWHM N Total exposure time
yyyy-mm-dd images s

2009-03-15 1.0 76 1140
2009-03-16 0.9 291 4365

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.

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