\begin{table}%t1
\par
\caption{Characteristics of the optical
 surveys used by CFBDS.
\label{maglim}}
%\centerline
 {
\begin{tabularx}{23cm}{XXXXXXXXX} \hline\hline
 Survey Name&  $z'$ detection limit & $i'$ detection limit & Mid-L
 detection range(pcs) & Early-T detection range(pcs) & Late-T detection range(pcs) & current coverage
 (sq deg)& final coverage(sq deg)&  Galactic $i'-z'$ Reddening\\ \hline  
 RCS-2            & 22.5  & 24.0 & 185 & 160 & 45  & 200 & 600 &  0.011~$\pm$~0.009 \\\hline
 CFHTLS Very Wide & 22.8  & 23.95 & 215 & 180 & 50  & 150 & 150  & 0.020~$\pm$~0.009\\\hline
 CFHTLS Wide      & 23.8  & 24.75 & 340 & 290 & 80 & 20  & 186  & $<$0.02 \\\hline
 CFHTLS Deep      & 24.5  & 26.25 & 470 & 400 & 110 & 3.8 to $z'=24.5$ & 3.8
 to $z'=26.3$ & $<$0.02 \\\hline
\end{tabularx}}
\par
\smallskip
 \mbox{The detection limits correspond to $10\sigma$, as needed for 
 10\% precision photometry.}
\end{table}