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Exit pupil/Eye relief
In the July edition of the Sky & Telescope there is an article on page 90 relating to eye aberrations and the use of EPs.
It has me confused as I was under the impression that, with age, we are not able to use the smaller aperture EPs because of our pupil loses its flexibility.
About a year ago I came back to astronomy after a break of a few years and (now aged 74) I have used a Barlow - with its drawback of loss of FOV- to help me with eye relief as I understood it. Recently I was advised to go for EPs that have a wide FOV but with a 20mm eye relief. However this article (in S&T) appears to me to refute the entire message about age and eye relief. (I have some understanding of the relationship between eye relief and exit pupil.)
The way I read it this expert is advocating the use of smaller apertures on EPs to counter eye aberrations.
I don't like using the Barlow because with eye at the EP I have to look around the edge of the view to take in only parts of the whole image at a time. Is this normal? Would the recommended EPs be the same?
If anyone has taken the time to read the subject article and has the knowledge to understand its meaning for us older blokes, I would be grateful for some understanding of its import to me as well as some guidance on EPs with long eye relief.
Cheers!
Bert
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