[AZ-Observing] Re: An Eyepiece for the LXD75 10" ?

>>  ...long focal length eyepiece for my f/4 Meade LXD75 10". A
>>  number of years ago I bought a 55mm University Plossel...
>>  ...focal length is so long that the I have to look around the shadow of the
>>  secondary.

     Do the "eyepiece math"!  A 55mm fl eyepiece in an f/4 optic
produces a 14mm exit pupil, and thus it is no surprise that you end up
seeing the secondary shadow.  If you assume "low power" means something
like a 5 to 7mm exit pupil, at f/4 this means an eyepiece between 20 and
28mm focal length.  Notice that this barely takes in the 26mm eyepiece
you rejected.  Do the arithmetic and consider again.  Remember also that
at f/4 you'll need a fancy eyepiece to get sharp images, but on the
other hand your eye is no good at large exit pupils, and one tends not
to use such eyepieces for very long while viewing.  So a super-sharp 
eyepiece may not be needed after all.
     A quick look at th ads in the latest S&T suggests there are 
a number of options among relatively cheap eyepieces with medium-wide
fields (~60 deg) for around $100 (Antares, Univ Optics, Meade, et al).

\Brian
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