\begin{table}%t1
\caption{\label{observations}Details of the observing runs (time is in minutes).}
%\centerline
 {
\begin{tabular}{llccc}
\hline\hline
 	  &  &  $U$   &  $B$  &  $V$  \\
\hline
\multirow{15}{*}{SDT} & 21 February 2007 &      & 60  &     \\
                      & 23 February 2007 &      & 30  &     \\
                      & 25 February 2007 &      & 60  &     \\
                      & 15 March 2007    &      &     & 54  \\
                      & 16 March 2007    &      &     & 114 \\
                      & 02 April 2007    &      & 30  &     \\
                      & 11 April 2007    & 30   & 30  &     \\
                      & 10 May 2007      & 60   &     &     \\
                      & 11 May 2007      & 54   &     &     \\
                      & 12 May 2007      & 54   &     &     \\
                      & 19 May 2007      & 90   &     &     \\
                      & 20 May 2007      & 60   &     &     \\
                      & 21 May 2007      & 36   &     &     \\
                      & 22 May 2007      & 60   &     &     \\
                      & 11 June 2007     & 60   &     &     \\
\hline
\multirow{9}{*}{LBTB} & 07 March 2008    & 90   & 120 & 120 \\
                      & 08 May 2008      & 168  &     &     \\
                      & 09 May 2008      & 78   &     &     \\
                      & 11 May 2008      & 240  &     &     \\
                      & 29 December 2008 &      & 60  & 60  \\
                      & 30 December 2008 & 60   & 54  & 30  \\
                      & 31 December 2008 & 63   &     &     \\
                      & 01 March 2009    &      & 69  & 69  \\
                      & 02 March 2009    & 51   &     &     \\
\hline
SDT                   &                  & 504  & 210 & 168 \\
LBTB                  &                  & 750  & 303 & 279 \\
Total                 &                  & 1254 & 513 & 441 \\
Effective             &                  & 828  & 333 & 321 \\
\hline
\end{tabular}}
\par
\medskip 
The SDT runs were made using the blue channel only, whereas the LBTB runs used
both telescopes. The effective exposure time is the time actually used
for the final stacks.
\end{table}