the contour at 50 % of the peak and deconvolved with the beam size. To determine the full diameter we determined the ratio of the flux density within the 3 $\sigma$ contour with the flux density within the 50 % contour. Hence, we assumed that the flux decreased linearly with radius outside the 50 % contour. We checked that this procedure seemed to give very good agreement with the size measured based on the 3 $\sigma$ contour. We didn’t use the contour level at 10% of the peak (Zijlstra et al. [@Zijlstra89], Aaquist & Kwok [@Aaquist90]), because this was often below noise level.

It was noticed in the review paper by Pottasch ([@Pottasch92]) that there is a selection against discovering both large and small PNe in the galactic bulge. 36 % of the new PNe have a diameter smaller than 5 , while this is 71 % for the known ones. The median is 66 for the new PNe and only 32 for the known bulge PNe with radio data. We seem to identify relatively more larger PNe than in previous surveys. In regions with large extinction the \[SIII\]$\lambda$9532 line appears efficient in picking out the larger, low surface brightness 