\begin{table}%t1
  \caption{Observation log.}\label{tab:obs}
%\centerline
{
  \begin{tabular}{l@{\hspace{0.5cm}}
      c@{\hspace{0.5cm}}
      c@{\hspace{0.5cm}}
      c@{\hspace{0.5cm}}
      c@{\hspace{0.5cm}}
    }
    \hline \hline
    Field & Time (UT) & Filter & $t_{\rm int}$ (s) & $\sec z$ \\
    \hline
    \multicolumn{5}{l}{December 11, 1996, LRIS} \\ 
    SA~95         & 08:23--08:25 & $R$ & $2+10$ & 1.07 \\
                   & 08:27--08:29 & $B$ & $2+10$ & 1.07 \\ 
    SA~95         & 09:28--09:31 & $B$ & $2+10$ & 1.07 \\
                   & 09:33--09:35 & $R$ & $2+10$ & 1.08 \\ 
    PSR~J0751+1807 & 09:45        & $R$ & $10$ & 1.39 \\
                   & 09:47--09:59 & $R$ & $2\times300$ & 1.36 \\
                   & 10:01        & $R$ & $600$ & 1.31 \\
                   & 10:13        & $B$ & $600$ & 1.26 \\ 
    \multicolumn{5}{l}{December 21, 2003, ESI} \\ 
    PSR~J0751+1807 & 10:06--10:27 & $R$ & $3\times360$ & 1.14 \\
                   & 10:29--10:57 & $I$ & $6\times240$ & 1.08 \\
                   & 11:00--11:33 & $B$ & $3\times600$ & 1.04 \\ 
    NGC~2419      & 11:40 & $B$ & $10+30$ & 1.06 \\
                   & 11:44 & $R$ & $10+30$ & 1.06 \\
                   & 11:47 & $I$ & $10+30$ & 1.06 \\       
    \multicolumn{5}{l}{January 7, 2005, LRIS} \\ 
    PSR~J0751+1807 & 11:54--12:53 & $R$ & $5\times600$ & 1.05 \\ 
    \multicolumn{5}{l}{January 8, 2005, LRIS} \\ 
    PSR~J0751+1807 & 11:42--12:51 & $R$ & $6\times600$ & 1.05 \\ 
    \multicolumn{5}{l}{January 26, 2005, NIRC} \\ 
    PSR~J0751+1807 & 08:06--08:56 & $K_{\rm s}$ & $36\times50$ & 1.07 \\ 
    2MASS star$^a$ & 08:59 & $K_{\rm s}$ & $0.4$ & 1.02\\
    \hline
  \end{tabular}}
  \medskip
 $^a$ 2MASS~J07510621+1807253.
\end{table}