Thanks very much Patrick and Suzy,
Yes the Argo really worked well that night with a fresh alignment on Sirius and Canopus. It put every object in the frame of the 9mm. I recently got some T-adapters for the 3 Nagler T6's, so they are all effectively 2", handy that because I only need one filter size.
It was interesting to compare the view through the UHC and O-III on the same object. The O-III really darkened the sky and made the PN stand out much better, but it tends to kill the faint field stars and central star unless it's bright.
Favourite ones apart from the ones you mentioned Suzy:
NGC 1535 Eri., NHC 2440 Puppis, NGC 5189 Musca, NGC 6302 Sco, NGC 7009 (Saturn) Aqr, IC418 Lepus (small), NGC 3918 Cen. Where to stop??? PN's have really become a favourite target with the O-III and 5mm Nagler. Good luck with the search.
There is a list OF PN's here:
http://www.atlasoftheuniverse.com/plannebs.html
Another interesting article on bipolar PN's: