  We present observations proving the close binary nature of the central stars
belonging to the planetary nebulae (PNe) NGC 6326 and NGC 6778. Photometric
monitoring reveals irradiated lightcurves with orbital periods of 0.372 and
0.1534 days, respectively, constituting firm evidence that they passed through
a common-envelope (CE) phase. Unlike most surveys for close binary central
stars (CSPN) however, the binary nature of NGC 6326 was first revealed
spectroscopically and only later did photometry obtain an orbital period.
Gemini South observations revealed a large 160 km/s shift between the nebula
and emission lines of C III and N III well known to originate from irradiated
atmospheres of main-sequence companions. These so-called weak emission lines
are fairly common in PNe and measurement of their radial velocity shifts in
spectroscopic surveys could facilitate the construction of a statistically
significant sample of post-CE nebulae. There is growing evidence that this
process can be further accelerated by pre-selecting nebulae with traits of
known post-CE nebulae. Both NGC 6326 and NGC 6778 were selected for their rich
attribution of low-ionisation filaments and collimated outflows, thereby
strengthening the connection between these traits and post-CE CSPN.
