\begin{table}%t3
%\centering
\par
\caption{Completeness and limiting magnitudes  and surface brightnesses
(mag arcsec$^{-2}$) derived from simulated  point-like and extended sources 
respectively. All values are in the AB system.}
\label{Tab:mags}
\begin{tabular}{cccc cc}
\hline\hline 
Pointing &
&
$m_{\rm comp}$ &
$m_{\rm lim}$ &
$\mu_{\rm comp}$ &
$\mu_{\rm lim}$  \\
 & &  (90\%) & (50\%) &  (90\%) & (50\%)\\
%\tabularnewline
\hline
1&
&
 25.0 &
 25.5 &
 25.7 &
 26.2 
\tabularnewline
2&
&
 24.9 &
 25.3 &
 25.8 &
 26.3 
\tabularnewline
3&
&
 24.9 &
 25.3 &
 25.7 &
 26.2  
\tabularnewline
\hline
\end{tabular} 
\end{table}