\begin{table}%t1
%\centering
\par
\caption{\label{Table6}Transmission values of the  Zeiss $K$~58 step filter from the observation log-books of the Arcetri Observatory.} 
\small \begin{tabular}{lcccccc}
\hline\hline\noalign{\smallskip}
$\lambda= 6000$~\AA           &100\%  & 72\%   & 45\%   & 28\%   & 19\%    &11\% \\
$\lambda= 4000$~\AA            &100\%  &  68\%  &  42\%  &  29\%  &  20\%   & 14\% \\
\hline
\end{tabular}
\end{table}