\begin{table}%T5 \par \caption{\label{photcal}Absolute photometric uncertainty and point source sensitivity.} \small %\centering \par \begin{tabular}{c c c c c } \hline\hline \noalign{\smallskip} Band & Uncertainty\tablefootmark{a} & Point source\tablefootmark{b} & Scan map\tablefootmark{b} & Parallel\tablefootmark{b}\\ & & mode & [$10'\times15'$] & $[120'\times120']$\\ & & $5\sigma$/1~h & $5\sigma$/30~h &$1\sigma$/3~h\\ \hline Blue & $\pm$10\% & 4.4~mJy & 3.7~mJy & 19.8~mJy\\ Green & $\pm$10\% & 5.1~mJy & 5.0~mJy & n.a.\\ Red & $\pm$20\% & 9.8~mJy & 9.5~mJy & 116~mJy\\ \hline \end{tabular} \tablefoot{\tablefoottext{a}{Derived from 33, 23 and 51 targets for blue, green and red point source observations respectively.}\\ \tablefoottext{b}{The noise values quoted in the table are instrument limited for the blue and green filter. The value for the red filter already contains confusion noise contributions (see text).}} \end{table}