A ring galaxy mate, awesome catch! On my list for next year's autumn clear night. Checked it out on Wikisky and that ring does appear to be very faint relative to the core. Impressive.
I too did some observing on those clear nights you mention and around sunset alot of putrid acrid-looking haze manifested itself toward the horizon. Looked almost like that famous Melbourne marine layer stratocrapulus junk setting in for the night. Although it seemed to clear up during the night, based on the visibility of stars relative to other nights. Seeing here was also extremely poor, the worst in a fair while.