\begin{table}%ta1
 %%\centering

\par
\caption{\label{tbl:speclog}Logbook of spectroscopic observations.}
\begin{tabular}{ccrr}
\hline\hline
Time (HJD-2~450~000)    & Instrument   & Exp. time (s) & $\langle {\it S/N}\rangle$\\
\hline
4748.77151 & C{\sc oralie} & 1800 & 45\\
4750.80021 & C{\sc oralie} & 1800 & 56\\
4751.79249 & C{\sc oralie} & 1800 & 25\\
4753.83953 & C{\sc oralie} & 1800 & 62\\
4755.86699 & C{\sc oralie} & 1800 & 69\\
4756.75304 & C{\sc oralie} & 1800 & 57\\
4758.76337 & C{\sc oralie} & 1500 & 61\\
4842.59491 & C{\sc oralie} & 1800 & 64\\
4842.67488 & C{\sc oralie} & 1800 & 64\\
4842.75034 & C{\sc oralie} & 1800 & 61\\
4843.58534 & C{\sc oralie} & 1800 & 65\\
4843.64708 & C{\sc oralie} & 1800 & 62\\
4843.79525 & C{\sc oralie} & 1800 & 60\\
4844.62333 & C{\sc oralie} & 1800 & 63\\
4844.70675 & C{\sc oralie} & 1800 & 64\\
4845.59027 & C{\sc oralie} & 1800 & 56\\
4845.77435 & C{\sc oralie} & 1800 & 51\\
4846.58948 & C{\sc oralie} & 1801 & 64\\
4846.68792 & C{\sc oralie} & 1801 & 66\\
4846.74996 & C{\sc oralie} & 1801 & 64\\
4847.58828 & C{\sc oralie} & 1801 & 64\\
4847.68662 & C{\sc oralie} & 1801 & 60\\
4848.61953 & C{\sc oralie} & 1800 & 60\\
4848.69951 & C{\sc oralie} & 1800 & 62\\
4850.61492 & C{\sc oralie} & 1800 & 59\\
4850.67672 & C{\sc oralie} & 1800 & 59\\
4851.59201 & C{\sc oralie} & 1800 & 57\\
4852.56425 & C{\sc oralie} & 1800 & 49\\
4852.62809 & C{\sc oralie} & 1800 & 60\\
4852.73125 & C{\sc oralie} & 1800 & 58\\
4912.55844 & C{\sc oralie} & 1800 & 59\\
4916.51655 & C{\sc oralie} & 1800 & 60\\
4918.54146 & C{\sc oralie} & 1801 & 58\\
4920.55779 & C{\sc oralie} & 1801 & 59\\
4922.55891 & C{\sc oralie} & 1801 & 57\\
5159.72850 & H{\sc ermes} &  420 & 27\\
5160.47824 & H{\sc ermes} & 1200 & 65\\
5162.53878 & H{\sc ermes} &  800 & 63\\
5162.54759 & H{\sc ermes} &  600 & 57\\
5162.77441 & H{\sc ermes} &  800 & 64\\
5162.78425 & H{\sc ermes} &  800 & 60\\
5167.68048 & H{\sc ermes} &  900 & 45\\
5167.69148 & H{\sc ermes} &  900 & 44\\ 
5167.78661 & H{\sc ermes} & 1200 & 54\\
5174.68443 & H{\sc arps}  &  620 & 141\\
5194.66678 & H{\sc arps}  &  800 & 169\\
\hline
\end{tabular}
\end{table}