\begin{table}%t3
%\centering
\par
\caption{\label{table3}The $B-R$ and $B-V$ values of the spherical structures and filament.}
\small \begin{tabular}{lcc}
\hline \hline
Structure & $B-R$& $B-V$ \\
 & (mag) & (mag) \\
\hline
 S sphere-like  &  2.913 & 1.829 \\
 SE sphere-like    & 2.694 & 1.636 \\
 Filament   & 2.839 & 1.672 \\
\hline
\end{tabular}
\end{table}