<"I take it from your comments that you’re using manual placement of AP’s around the ring as Daryl describes? I’ll have to try that. My recent results, while using much smaller AP’s (size 30 multi scale) I’ve been allowing AS!3 to place them for me.">
...just on this & your comments in your other thread, let's hope you get on top of all this soon, though there should still be a lot of imaging opportunities in both planets' apparitions...the comments I've quoted here are a "sometimes" cure for a split Cassini Division at the ansae where a particular type of nasty "vibrating" seeing can induce said: there are other times when it is due to other problems - but placing a ring of small MAPs along the rings can help some of the time - & other times not!
Being an old dinosaur I always manually apply the MAPs boxes, suspicious of auto-placement...although I'm sure many folks employ auto without any problems.
At any rate, from our conversation I felt it was worthwhile to elaborate on the collimation situation with you - I hope that astigmatism isn't an issue as I understand that in SCT's this is something incurable -
But I'm sure you'll get to the bottom of it all!