Re: [ATM] Eyepiece Question

["John Sherman" <atmer@johnspics.com>]

>Enough to justify their expense? I would appreciate
> comments from more experienced observers.

Hi Gil,

Yes a Nagler has a wider field, and maybe a bit more eye relief.  But!  When 
you are after hi-res planet viewing you need to observe when the object is 
near the center of the field. An F/5 will have a significant amount of coma 
away from the optical axis, and you'll probably find that most eyepieces 
also have problems away from their axis.

A Plossl might be a better eyepiece than a Nagler for hi-res viewing, 
because the Nagler has lots of elements and surfaces (also, I've heard the 
Naglers, etc, sacrifice the center of the field slightly in order to sharpen 
up the edge a bit).

What I do is guide my scope by hand. I lay my arm on my ladder for support, 
and with my hand I put just enough pressure on the scope so that it keeps 
moving slowly. This way I can keep the planet at the center of the field for 
a longer time. More important than buying a Nagler are good seeing, good 
collimation, and very careful focussing.

John






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