\begin{table}%t2
\caption{\label{tab:coeff} Mean photometric calibration coefficients for our WFC-INT observing run.}
\small
%\centerline
 {\begin{tabular}{cccc}  
\hline\hline\noalign{\smallskip}
Filter & {\it K}\tablefootmark{\dagger} & {\it ZP} & {\it c} \\
%\noalign{\medskip}
\hline
%\noalign{\medskip}
$R$   &  0.0734 & $25.30\pm0.03$ & $-0.033\pm0.024$  \\
$Z$   &  0.0103 & $23.52\pm0.03$ & $ 0.021\pm0.022$  \\
%\noalign{\medskip}
\hline
\end{tabular}}
\tablefoot {\tablefoottext{\dagger} {{\it K} = mean atmospheric extinction coefficients for La Palma.}\\
\tablefoottext{\ddagger}{{\it ZP} = photometric zero point (see Eq.~(\ref{cal_RZ})).} 
\tablefoottext{*} {{\it c} = photometric colour term (see Eq.~(\ref{cal_RZ})).}}
\end{table}