\begin{table}%t1
\caption{Magnitudes of the secondary standard stars. The "--'' signs 
appear where the magnitudes for the stars have not been derived either 
because they were saturated in some images, which was the case of the 
B and C~stars, or they were faint and therefore gave large photometric 
errors ($>$$0.08$). These were disregarded in the case of the $U$, $B$, and 
near-IR bands of the secondary standards~1--6. The $V\!RI$~band magnitudes 
of~A, B, C, and~D are taken from \citet{sahu00}.}
\label{tab:712_field}
%\centering
\par
\begin{tabular}{lllllllll}
\hline \hline 
Std. &   $U$ & $B$ & $V$ & $R$ & $I$ & $J$ & $H$ & $K\!s$  \\
\hline 
1& -- &  -- & 19.84 $\pm$ 0.02 & 18.76 $\pm$ 0.02 & 17.48 $\pm$ 0.03 &-- &--&--\\
2&19.16 $\pm$ 0.07& -- & 18.21 $\pm$ 0.01 &17.87 $\pm$ 0.02 & 17.48 $\pm$ 0.03&-- &--&--\\
3&--&--& 19.08 $\pm$ 0.02     &17.94 $\pm$ 0.02  &16.57 $\pm$ 0.03 &-- &--&--\\
4&--&--&18.90 $\pm$ 0.02  &18.37 $\pm$ 0.02  & 17.86 $\pm$ 0.03&-- &--&--\\
5&--&--&20.72 $\pm$ 0.04  &19.73 $\pm$ 0.02  &18.68 $\pm$ 0.04&-- &--&--\\
6&--&--&19.21 $\pm$ 0.01  &18.31 $\pm$ 0.02   &17.34 $\pm$ 0.03&-- &--&--\\
A&18.80 $\pm$ 0.06 & 18.80 $\pm$ 0.06 & 17.16 $\pm$ 0.01 & 16.40 $\pm$ 0.01& 15.64 $\pm$ 0.01 & 14.82 $\pm$ 0.02 & 14.20 $\pm$ 0.03 & 14.04 $\pm$ 0.04\\ 
B& --& 17.91 $\pm$ 0.05 & 16.98 $\pm$ 0.01& 16.65 $\pm$ 0.01 & 16.29 $\pm$ 0.01
 & 15.91  $\pm$  0.02 & 15.60  $\pm$  0.04 & 15.57 $\pm$ 0.03\\
C& --& 17.69 $\pm$ 0.07 & 16.46 $\pm$ 0.01& 15.97 $\pm$ 0.01 & 15.50 $\pm$ 0.01
& 14.96 $\pm$ 0.02 & 14.51 $\pm$ 0.04 & 14.42 $\pm$ 0.04\\
D&17.69 $\pm$ 0.07& 17.33 $\pm$ 0.06 & 15.91 $\pm$ 0.01 & 15.27 $\pm$ 0.01 & 14.65 $\pm$ 0.01  
& 13.99 $\pm$ 0.02 & 13.39 $\pm$ 0.03 & 13.28 $\pm$ 0.03\\
\hline
\end{tabular}
\end{table}