I looked at the planetary nebulae NGCs 7293, 1360, 246, 1514, IC 5150, NGCs 2818, 2440, 2438, 1535, 2392, 7662, 7009 and 6818 this morning. (listed from large to small). I also looked at Abell 21 with a 12" Dob and a 21mm EP. Abell 21 was large and very faint with an OIII filter and with a UHC filter.
The attached wikisky image shows Abell 21 with a 28' field. Wikisky.org images of all the NGC PN are at
https://picasaweb.google.com/1100488...Jm95-XF98SCggE