\begin{table}%t1
\par
\caption{\label{tabsp}Spectral resolution ($R$) and bandwidth ($\Delta\lambda$) of the VEGA spectrograph, as well as the spectral separation between the two detectors.}
  \small%\centering
\par
  \begin{tabular}{rcrrr}
  \hline\hline
   {Grating} & ${R}$ &  {$\Delta\lambda$ (Blue)} &  $\Delta\lambda$ (Red)  &  $\lambda_R-\lambda_B$  \\
  \hline
  R1: 1800~gr/mm & 30~000 & 5 nm & 8 nm & 25 nm\\
  R2: 300~gr/mm & 5000 & 30 nm & 45 nm & 170 nm \\
  R3: 100~gr/mm & 1700 & 100 nm & 150 nm & not possible\\
  \hline
  \end{tabular} 
  \end{table}