\begin{table}%t1
\caption{\label{tab:ext}Log of the simultaneous ground-based observations of HD~261387 using the OSN 0.9~m telescope and Str\"omgren $\it uvby$~filters.}
\par
%\centering
\small
\begin{tabular}{lcr}
\hline\hline
\multicolumn{1}{c}{Date} & \multicolumn{1}{c}{Timebase [h]} &
\multicolumn{1}{c}{Points}\\
\hline
\multicolumn{3}{c}{December 2006}   \\
15--16    &    2.9&                32\\
16--17        &    3.9&           37\\
17--18        &    2.6&            31\\
18--19        &    2.9&           28\\
19--20        &    3.3&            28\\
20--21        &    2.5&            26\\
21--22        &    3.3&            44\\
\hline
\multicolumn{3}{c}{January 2007}   \\
09--10    &    2.1&                32\\
11--12        &    5.5&            33\\
12--13        &    5.7&            79\\
16--17        &    6.2&            42\\
17--18        &    6.1&            90\\
18--19        &    5.7&            89\\
19--20        &    6.8&           80\\
20--21        &    7.7&            105\\
\hline
\end{tabular}
\end{table}