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Hi Joe,
Eyeglass scrips don't change much, so when I'd get a new set of eyeglasses I'd ask the people at the shop if they could cut the old eyeglass lenses down to circles, and put a notch on top for the right eye and two notches for the left eye. This they did. Then I stuck the lenses onto eyepieces or into binoculars with Blutack.
But I only had 1.25" eyepieces back then, and I only stuck and left the lenses on my 40mm eyepiece, and into my 10x70 binoculars - where they still are. My astigmatism isn't so bad at a 3mm or less exit pupil, so that when I tried sticking the eyeglass lenses to 32mm and 26mm eyepieces, while they worked, it seemed more effort than what it was worth having to constantly rotate the position of the eyepiece in my C8's diagonal as I moved around the sky.
I did discover another method to get rid of astigmatism in my 14.5" dob. Instead of going down to a 6 or 7mm exit pupil which gave me a view with very bad astigmatism, I went down to a 9mm exit pupil instead. Thus I could easily twist my eye to a position where the astigmatism disappeared, without blanking out part of the image (as would have been the case with the 6 or 7mm exit pupils).
You are dead right about the need for multicoatings as far as I am concerned, though some people don't seem to notice the internal reflections on uncoated eyeglass lenses - which I find strange as they drive me batty.
Regards,
Renato
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