\begin{table}%t1
%\centering
\par
\caption{\label{visir_log}Log of the observations of $\delta$~Vel and its calibrators,  \object{HD 82668}, \object{HD 67582} and \object{HD 80007} with VISIR. MJD$^*$ is the modified Julian date of the middle of the exposures on the target, minus 54~580. The Detector Integration Time (DIT) is given in milliseconds for one BURST image. $\theta$ is the seeing in the visible ($\lambda=0.5~\mu$m) as measured by the observatory DIMM sensor, in arcseconds. $N$ exp. is the number of selected and averaged exposures. The airmass (AM) is the average airmass of the observation.} 
\par
\begin{tabular}{cccccccc}
\hline \hline
\# & MJD$^*$ & Star & Filter & DIT & $N$ exp. & $\theta$~($\arcsec$) & AM \\
\hline
A & 0.0134 & $\delta$~Vel & PAH1 & 20 & 10~000 & 0.86 & 1.18 \\
B & 0.0231 & $\delta$~Vel & PAH1 & 20 & 10~000 & 1.00 & 1.20 \\
C & 0.0374 & HD~82668 & PAH1 & 20 & 5000 & 1.10 & 1.20 \\
D & 0.0603 & HD~67582 & PAH1 & 16 & 10~000 & 0.84 & 1.30 \\
E & 0.0774 & $\delta$~Vel & PAH1 & 16 & 8000 & 0.70 & 1.33 \\
F & 0.0874 & $\delta$~Vel & PAH1 & 16 & 8000 & 0.67 & 1.37 \\
G & 0.0977 & $\delta$~Vel & PAH2 & 8 & 10~000 & 0.60 & 1.42 \\
H & 0.1093 & $\delta$~Vel & PAH2 & 8 & 12~000 & 0.53 & 1.48 \\
I & 0.1206 & $\delta$~Vel & PAH2 & 8 & 10~000 & 0.80 & 1.54 \\
J & 0.1363 & HD~67582 & PAH2 & 8 & 10~000 & 1.15 & 1.92 \\
K & 0.1480 & HD~67582 & PAH2 & 8 & 10~000 & 1.50 & 2.09 \\
L & 0.1632 & $\delta$~Vel & NeII & 16 & 10~000 & 1.29 & 1.91 \\
M & 0.1860 & HD~80007 & NeII & 16 & 10~000 & 1.12 & 1.46 \\
N & 0.1979 & HD~80007 & NeII & 16 & 10~000 & 1.00 & 1.52 \\
\hline
\end{tabular}
\end{table}