Palm Beach looks good because of its relative isolation and it has the NP behind it but it is only ~40km from the CBD. I would have thought some places in the Royal NP would be at least as good. There were some good Comet Lovejoy shots taken from just north of Bald Hill. Further south it starts to get dark south of Kiama. We went out to Black Point at Gerroa for Lovejoy and it would have been fine to look to the east except for the cloud. Seven Mile Beach would also be good. We also tried Saddleback Mtn Lookout just inland from Kiama and it was dark to the south but the northern horizon is a bit blocked and has a bit of light. By the time you reach Jervis Bay it is quite dark.
Being a local I know these sites quite well but because I go inland for my astronomy I have less direct experience with the seeing but I still think my assessment is reasonable. If they want to speak to me directly please pm for my contact details. Note that I'll be away for three weeks from 1 Nov enjoying the clear mornings in FNQ

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