\begin{table}%t1
\caption{\label{tab:plates}Main characteristics of the plate
material utilized for the construction of the GSC-II. }
%\centering
\par
\begin{tabular}{lccll}
\hline\hline
  Survey&Epoch&Emulsion&Band&Depth \\
            &     &+filter  \\
\hline
    Pal-QV    & 1983--85 & IIaD+W12    & $V_{12}$  & 19.5\\
    SERC-J    & 1975--87 & IIIaJ+GG395 & $B_{J}$ & 23.0   \\
    SERC-EJ   & 1979--88 & IIIaJ+GG395 & $B_{J}$ & 23.0   \\
    POSS-I E  & 1950--58 & 103aE+red   &   E  & 20.0   \\
    POSS-I O  & 1950--58 & 103aO       &   O  & 21.0   \\
    POSS-II J & 1987--00 & IIIaJ+GG385 & $B_{J}$ & 22.5   \\
    POSS-II F & 1987--99 & IIIaF+RG610 & $R_{\rm F}$  & 20.8   \\
    POSS-II N & 1989--02 & IV-N +RG9   & $I_{N}$  & 19.5   \\
    AAO-SES   & 1990--00 & IIIaF+OG590 & $R_{\rm F}$  & 22.0   \\
    SERC-ER   & 1990--98 & IIIaF+OG590 & $R_{\rm F}$  & 22.0   \\
    SERC-I    & 1990--02 & IV-N +RG715 & $I_{N}$  & 19.5   \\
    M W Atlas & 1978--85 & IV-N +RG715 & $I_{N}$  & 19     \\
    SERC QV   & 1987--88 & IIaD +GG495 & $V_{495}$  & 14   \\
    AAO SR    & 1996--99 & IIIaF+OG590 & $R_{\rm F}$  & 20     \\
\hline
\end{tabular}
\end{table}