Thanks Asi It was a wierd night, as I said the stars were twinkling so much that I nearly didn't bother, then the very next night it looked much better till I put the camera on and all I had was a boiling mess (at least I got some sleep )
I've been having all sorts here Rob. If I were going by how much twinkle I see naked eye, I'd just give an evil laugh & go to bed or something but every time I decide to ignore what I see & just setup anyway, the lappy proves to me that in fact, naked eye twinkle is not something to be relied upon.