\begin{table} %t2
\caption{\label{tab2}Journal of observations of NGC~1582, NGC~1663 and standard star fields 
together with calibration coefficients (November 8, 2002).}
 {
%\centering
\par
\hspace{2mm}\begin{tabular}{ccccccc} 
\hline \hline 
\multicolumn{1}{c}{Field}         & 
\multicolumn{1}{c}{Filter}        & 
\multicolumn{3}{c}{Exposure time} & 
\multicolumn{1}{c}{Seeing}        &
\multicolumn{1}{c}{Airmass}       \\
 & & \multicolumn{3}{c}{[s]} & [$\prime\prime$] & \\ 
\hline 
 NGC 1582       & $U$ &  $900\times 2$ & 180 & 20 & 2.5 & 1.196 \\ 
                & $B$ &  600   &  60 & 10 & 2.3 & 1.230 \\ 
                & $V$ &  300   &  30 &  5 & 2.4 & 1.255 \\ 
                & $I$ &  300   &  30 &  5 & 2.1 & 1.274 \\
\hline
 NGC 1663       & $U$ &  $900\times 2$ &   -- &  -- & 2.5 & 1.348 \\ 
                & $B$ &  600   &  60 &  -- & 2.4 & 1.215 \\ 
                & $V$ &  300   &  30 &  3 & 2.2 & 1.188 \\ 
                & $I$ &  300   &  30 &  3 & 2.0 & 1.190 \\
\hline
PG 0231+051     & $U$ &  800   &     &    & 2.5 & 1.348 \\
                & $B$ &  300   &     &    & 2.4 & 1.324 \\ 
                & $V$ &   60   &     &    & 2.2 & 1.316 \\ 
                & $I$ &   90   &     &    & 2.2 & 1.315 \\ 
\hline
PG 2213-006     & $U$ &  600   &     &    & 2.5 & 1.447 \\
                & $B$ &  150   &     &    & 2.3 & 1.457 \\ 
                & $V$ &   30   &     &    & 2.3 & 1.465 \\ 
                & $I$ &   30   &     &    & 2.3 & 1.472 \\ 
\hline 
\hline
Calibration     & \multicolumn {3}{l}{$u_1 = +3.861 \pm 0.015$}     & \multicolumn {3}{l}{$b_1 = +1.602 \pm 0.004$} \\
coefficients    & \multicolumn {3}{l}{$u_2 = -0.142 \pm 0.022$}     & \multicolumn {3}{l}{$b_2 = +0.038 \pm 0.006$} \\
                & \multicolumn {3}{l}{$u_3 = +0.58$}                & \multicolumn {3}{l}{$b_3 = +0.29$}            \\
		& \multicolumn {3}{l}{$v_{1bv} = +1.003 \pm 0.014$} & \multicolumn {3}{l}{$i_1 = +1.691 \pm 0.044$} \\
		& \multicolumn {3}{l}{$v_{2bv} = -0.016 \pm 0.018$} & \multicolumn {3}{l}{$i_2 = +0.057 \pm 0.043$} \\
		& \multicolumn {3}{l}{$v_3 = +0.16$}                & \multicolumn {3}{l}{$i_3 = +0.08$}            \\
		& \multicolumn {3}{l}{$v_{1vi} = +1.002 \pm 0.016$} & \\
		& \multicolumn {3}{l}{$v_{2vi} = -0.013 \pm 0.016$} & \\
\hline
\end{tabular}}
\end{table}