\begin{table}%t1
\caption{\label{tab:rates}Observed fields and spectroscopic confirmations.}
%\centerline
 {\begin{tabular}{cccc}
\hline\hline 
Field  &  F7\_1       &  F7\_2       &  F4      \\  %  &  LPE         &  RCN1        \\
\hline
$\alpha$(J2000.0) &  12 28 53.70 &  12 28 46.40 &  12 27 43.35 \\ % &  12 17 34.26 &  12 26 08.00 \\
$\delta$(J2000.0) & +12 44 32.5  & +13 00 20.5  & +12 33 57.5  \\ % & +13 50 44.5  & +14 05 52.8  \\
$N_{\rm tot}^a$           & 22           &  28          &  25          \\ % &  10          &  43          \\
$N_{\rm cmp}^b$           & 13           &  12          &   8            \\
$N_{\rm em}^c$          & 9            &  5           &   5          \\ % &   1          &  1           \\
$N_{\rm PN}^d$          & 6            &  4$^e$       &   3          \\ % &   1          &  1           \\
\hline
\end{tabular} }
\par
\smallskip
$^a$ Total number of targets with allocated fibers.\\
$^b$ Number of targets with allocated fibers and $m_{5007}$ brighter
or equal to the completeness magnitude limit of the photometric
survey.\\
$^c$ Number of spectra with detected emission { line}.\\
$^d$ Number of spectra with both \Oiii$\lambda~ 4959,~5007$~\AA\ detected.\\
$^e$ One of these is in common with F7\_1, i.e., we have only~12
confirmed PNs in total, one of which was observed twice.
\end{table}