\begin{table}%t2
\par
\caption {\label{masks}Characteristics of the images used to produce the
  foreground object's mask for each cluster field.} 
%\centerline
 {\begin{tabular}{llllllll}
\hline\hline
\noalign{\smallskip}
Cluster & Instrument and reference & Filter & Exposure time & Depth
(5$\sigma$, AB) & Mask area $6\arcmin \times 6\arcmin$, & 
$2.2\arcmin\times2.2\arcmin$, &
$0.85\arcmin \times0.85\arcmin$ \\ 
\hline
Abell 1689 & ISAAC/VLT \citet{Moorwood97} & SZ & 14.4 ks & 26.0 & 7\% & 12\% & 10\%   \\
Abell 1835 & FORS/VLT  \citet{Appenzeller} & V  & 19.6 ks & 27.0 & 6\% & 10\% & 8\%   \\
AC114      & SOFI/NTT  \citet{Moorwood98} & K  & 10.8 ks & 22.0 & 6\% & 9\% & 7\%   \\
\hline
\end{tabular}}
\tablefoot{The three last columns
  representing the fractional surface area covered by the foreground galaxies
  in each cluster, for the three reference field of view, EMIR-like, JWST-like
  and NICMOS-like respectively.}
\end{table}