\begin{table} %t1 
             \caption{\label{tabla1}Journal of optical observations of the \object{GRB~051028} field.}
             \small%\centering
\par
                     \begin{tabular}{@{}lcccc@{}}  
  \hline\hline
Date of 2005 UT & Telescope/ & Filter & Exposure Time & Magnitude\\  
(mid exposure)  & Instrument &        &    (s)  &          \\  
\hline  
Oct. 28,  16:18   & 2.0 HCT (HFOSC)  & $R_{\rm c}$ &     300   &  20.63~$\pm$~0.04 \\
Oct. 28,  16:32   & 2.0 HCT (HFOSC)  & $R_{\rm c}$ &     300   &  20.72~$\pm$~0.05 \\
Oct. 28,  16:47   & 2.0 HCT (HFOSC)  & $R_{\rm c}$ &     300   &  21.14~$\pm$~0.07 \\
Oct. 28,  17:03   & 2.0 HCT (HFOSC)  & $R_{\rm c}$ &     300   &  21.27~$\pm$~0.07 \\
Oct. 28,  17:43   & 1.34 Taut (CCD)  & $R_{\rm c}$ &   1080  &  21.23~$\pm$~0.13 \\
Oct. 28,  17:47   & 2.0 HCT (HFOSC)  & $R_{\rm c}$ &     300   &  21.17~$\pm$~0.08 \\
Oct. 28,  21:42   & 4.2 WHT (PFC)    & $R$     &     300   &  21.97~$\pm$~0.05 \\
Oct. 29,  05:47   & 4.2 WHT (PFC)    & $R$     &     120   &  22.8~$\pm$~0.3   \\
Oct. 29,  20:15   & 4.2 WHT (PFC)    & $R$     &     720   &    $>$23.7      \\
Oct. 31,  22:14   & 4.2 WHT (PFC)    & $R$     &   2700  &    $>$25.1      \\
\hline
Oct. 28,  16:25   & 2.0 HCT (HFOSC)  & $I_{\rm c}$ &     300   &  19.79~$\pm$~0.11 \\
Oct. 28,  16:39   & 2.0 HCT (HFOSC)  & $I_{\rm c}$ &     300   &  19.94~$\pm$~0.06 \\
Oct. 28,  16:55   & 2.0 HCT (HFOSC)  & $I_{\rm c}$ &     300   &  20.29~$\pm$~0.09 \\
Oct. 28,  17:09   & 1.34 Taut (CCD)  & $I_{\rm c}$ &   1080  &  20.5 ~$\pm$~ 0.3 \\
Oct. 28,  17:10   & 2.0 HCT (HFOSC)  & $I_{\rm c}$ &     300   &  20.38~$\pm$~0.08 \\
Oct. 28,  17:55   & 2.0 HCT (HFOSC)  & $I_{\rm c}$ &     300   &  20.35~$\pm$~0.09 \\
Oct. 28,  19:12   & 1.34 Taut (CCD)  & $I_{\rm c}$ &   1800  &  20.67~$\pm$~0.23 \\
Oct. 28,  20:33   & 1.34 Taut (CCD)  & $I_{\rm c}$ &   3600  &  20.75~$\pm$~0.13 \\
Oct. 28,  22:50   & 1.34 Taut (CCD)  & $I_{\rm c}$ &   5400  &  21.16~$\pm$~0.16 \\
\hline
Oct. 28,  18:28   & 1.34 Taut (CCD)  & $V$     &   1080  &  22.08~$\pm$~0.20 \\
\hline  
 \end{tabular}  
 \end{table}