\begin{table}%t1
\caption{\label{tab:obs}Summary of the observations.}
\small%\centering
\par
\begin{tabular}{lrr}
\hline\hline\noalign{\smallskip}
Filter          & $g'$    & $r'$ \\     
\hline
Number of coadded images & 5   & 8 \\
Exposure time (s)   & 2000  & 4000  \\
Seeing (arcsec)     & 0.81  & 0.73 \\
Limiting magnitude (5$\sigma$) & 26.7 & 26.4 \\
\hline
\end{tabular} 
\end{table}