\begin{table}%t3
\caption{\label{ta:data:ccdmask}Lower and upper $\sigma$ thresholds for pixel masking with
  \texttt{ccdmask} in the bias variance and the sky-subtracted and
  object-masked median images.
\vspace*{-1.5mm}}
\small%\centering
\par
\begin{tabular} {lll}
\hline\hline\noalign{\smallskip}
Image type & \texttt{lsigma} & \texttt{hsigma} \\
\hline
Bias variance & 100 & 25, +5 if more than 2.5\% masked\\
Median, gain = 1 & 13 & 11\\
Median, gain = 2\tablefootmark{a} & 15 & 15\\
\hline
\end{tabular}
\vspace*{-1.5mm}
\tablefoot{\tablefoottext{a}{The COSMOS images were taken with
  \mbox{${\rm gain}=1$}, whereas the \mbox{${\rm gain}=2$} setting has been applied
  for some of the  HAGGLeS fields (Marshall et al.\thinspace2010,
  in prep.). While we do not include these fields in the current analysis,
  they have been processed with the same pipeline upgrades described here. Thus, we list
  these values for completeness.}}
  \vspace*{3mm}
\end{table}