Eye Relief

Since its cloudy, I have a question that's been a curiosity for some time, now. I'm a glasses wearer that has relatively astigmatic-free eyes. So I optionally wear glasses depending on the type of object I'm observing.

Has anyone considered what the "sweet spot" is with respect to eye relief with and without glasses? I know that 40mm eye relief provided by my 55mm Plossl is too long to be comfortable in either mode.

Anybody have an opinion they care to share?

Thanks!

Blake, I wear glasses and find that eye relief of 11-15mm is comfortable with my glasses on.

Any of the eyepieces built with the kinda sorta standard 20mm eye relief for eyeglasses, I've found to work well.
They're not all exactly on perhaps, but if the maker is trying for close to that, then they usually work better the those ep's with just a large eye lens.