Rod,
I was able to observe both E and F in my 6" newt when conditions were favourable, which I guess was maybe 1 night in 6 observing. E was not so difficult in the 6" scope. In my 8" scope I was able to get them both 50 to 70% of the time and in my 10" scope I probably get them about 90% of the time. There are some tricks/techniques to observing them that help.
Wait till they are high in the sky, don't waste your time low down.
Good transparancy is paramount, it is more important than good seeing but good seeing and transparency makes it a whole lot easier.
You need to use the right eyepiece to get the correct mag to suit your particular scope. In a 6" to 8" scope you need about 150X on average, in a 10" scope they sometimes "pop in"a bit lower than this so between 120x and 160x is good on most nights. You need sufficient mag to get the necessary separation in your scope but not too much mag as they can disappear again as you increase the mag to high. Under excellent conditions the eyepiece parameters are not quite so critical. In your own 10" SCt I would be aiming to use an eyepiece between 16mm and 20mm if you have one, a good quality high transmission eyepiece always helps as opposed to a $30 made in PRC eyepiece.
I plan to attend our Central Coast observing session on 9/4 and I can expand a little more on this if you want on that night.
Cs-John B
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