\begin{table}%t2
\caption{Redshifts and photometric data of the sources in Subsample~Two.}\label{t_optical}
%\centerline
{
\begin{tabular}{llcl|cc|ccccc}
\hline \hline
\multicolumn{1}{c} {Source} &
\multicolumn{1}{c} {$z$} & {Ref.} & {Opt.} &
\multicolumn{2}{c|} {APM} &
\multicolumn{5}{c} {SDSS/DR4} \\
\multicolumn{1}{c} {name} & & & \multicolumn{1}{c|} {ID} & $R$ & $B$ & $u$ & $g$ & $r$ & $i$ & $z$\\
\multicolumn{1}{c} {(1)} & \multicolumn{1}{c} {(2)} &
(3) & \multicolumn{1}{c|} {(4)} & (5) & (6) & (7) & (8) & (9) & (10) & (11) \\
\hline
0744+291 &       &     & q    & 19.70 & 19.79 & 21.04 & 20.91 & 20.98 & 20.64 & 20.14\\
0747+314 &       &     & G    &       &       & 22.55 & 23.55 & 20.87 & 19.02 & 19.24\\
0811+360 &       &     & EF   &       &       &       &       &       &       &      \\
0853+291 & 1.085 & (5) & Q    & 18.45 & 18.79 & 18.99 & 18.91 & 18.67 & 18.69 & 18.79\\
0902+416 &       &     & G    &       &       & 22.55 & 22.67 & 21.77 & 21.07 & 20.27\\
0922+322 &       &     & G    &       &       & 23.55 & 22.71 & 22.32 & 22.08 & 21.70\\
1123+340 & 1.247 & (1) & G    &       &       &       &       &       &       &      \\
1242+364 &       &     & G    &       &       & 23.87 & 21.94 & 21.57 & 21.23 & 20.30\\
1251+308 &       &     & -- & 19.67 & 21.14 &       &       &       &       &      \\
1343+386 & 1.844 & (2) & Q    & 17.69 & -- & 18.42 & 18.24 & 18.05 & 17.60 & 17.52\\
1401+353 & 0.45$\dagger$ & (3) & q    & 19.40 & 20.32 & 21.09 & 20.35 & 19.86 & 19.54 & 19.02\\
1441+409 &       &     & EF   &       &       &       &       &       &       &      \\
1601+382 &       &     & G    & 18.45 & 20.96 & 21.42 & 19.60 & 18.23 & 17.66 & 17.24\\
1619+378 & 1.271 & (4) & Q    & 18.89 & 21.29 & 21.29 & 19.90 & 18.81 & 18.29 & 18.00\\
1632+391 & 1.085 & (5) & Q    & 17.93 & 18.33 & 18.95 & 18.68 & 18.34 & 18.21 & 18.04\\
1656+391 &       &     & G    &       &       & 24.08 & 22.04 & 20.26 & 19.56 & 19.13\\
1709+303 &       &     & EF   &       &       &       &       &       &       &      \\
\hline
\end{tabular}}
\medskip
Description of the columns:
Col.~(1): source name in the IAU format;
Col.~(2): redshift;
Col.~(3): reference for the redshift given in Col.~2;
Col.~(4): optical identification: G~-- galaxy, Q~-- QSO, EF~-- "empty field'',
q~-- a~star-like object with no known redshift;
Cols.~(5 and~6): magnitudes for the two~POSS/APM colours;
Cols.~(7--11): magnitudes for the five SDSS~colours. \\
$\dagger$ Photometric redshift. \\
References for redshifts:
(1)~-- \citet{rel01}, (2)~-- \citet{hb89}, (3)~-- \citet{mach98},
(4)~-- \citet{kock96}, (5)~-- SDSS.\\
Sources~1232+295 and 1717+315 are not listed since there is no data
available for them to date and their possible
optical counterparts are too faint to be measured using APM.\\
Note for optical identifications: "G'' should be treated with caution as these
designations mostly come from the "automated classifier'' of~SDSS.
\end{table}