\begin{table}%t4
  %\centering
\par
  \caption{Current, potential, and achieved limiting magnitudes of AMBER in the $K$~band, for $50~\mbox{ms}$ frames.}\label{tab:magnitudes}
  \begin{tabular}{lcccc}
    \hline\hline
    Mode & MR & MR & LR & LR \\
    Conditions & best 20\% & average & best 20\% & average \\
  \hline
  Current   & 5.6 & 4.9 & 10.2 & 9.7\\
  Potential  & 6.8 & 6.1 & 11.5 & 10.9\\
  \hline
  Achieved  & -- & 4.9 & -- & 8.6\\
  \hline
  \end{tabular}
\end{table}