\begin{table}%t1
\caption{\label{t:obs}Summary of LBT observations of the field of RBS1774.}
\small%\centerline
 {
\begin{tabular}{lrrr}
\hline \hline
Date & Frames $\times$ exposure & Exposure tot & $b_0$\\
YYYYMMDD&&(s) \\
\hline
20071012 & $10\times300$ & 3000 & 27.68\\
20071014 & $10\times300$ & 3000 & 27.61\\
20071015 & $ 5\times300$ & 1500 & 27.61\\
20071016 & $16\times300$,$10\times150$ & 6300 & --\\
20071018 & $ 2\times150$ &  300 & 27.62\\
\hline
\end{tabular}}
\medskip
All exposures were taken through a Bessel $B$-filter. The last column gives the nightly photometric zeropoint.
\end{table}