[Wavytone]

Mark, I'm quite sure it would - in good seeing. Likewise I had the chance to observe Jupiter and Saturn several times with the old Reynolds at Stromlo (a 30" f/15 Cassegrain) between photometry assignments - likewise it was staggering.

The trouble is, the seeing at observatory hill is not good and it has 3-4 magnitudes of light pollution, so to be perfectly frank any telescope there is just a MUSEUM PIECE, not something anyone will use for serous observations of anything.

I used to live at Waverton across the other side of the harbour and I tried observing from Observatory Hill, Balls Head and Berry Island several times but gave it away because the seeing was invariably poor. In 4 years I never saw what I would describe as good seeing above 6/10.

Where I am now on the ridge in Killara there is often a NE sea breeze in the evening bringing laminar flow and this makes a HUGE difference, at least good views of the planets are possible with my 7" on many nights.

As for the effect of central obstruction I'll do the maths and post some charts so you can see. I don't agree with you on that score.