Re: [ATM] Eyepiece Question

[Alexis Cousein <al@sgi.com>]

G Gagne wrote:
> I'm in need of a short focus eypiece to replace a 7.5mm plossl for my 
> 12" f/5.6 non-tracking dob. Whenever I used the 7.5mm eyepiece the field 
> of view seemed quite small with not much eye relief 

Valid concerns. If you want to see if something with better eye relief
and more field is for you, I'd suggest picking up a Burgess Optical/TMB
Planetary; they're not too expensive and you'll see whether you like
these types of eyepieces or not.

> and whatever object 
> I was viewing quickly drifted out of the field of view.

It's an ATM list, so the proper suggestion here would be to build
your own equatorial platform for that part ;).

 > but do the
> more expensive eyepieces like Televue give you larger fields of view and 
> greater eye relief?

and/or. Well, almost anything gives more eye relief than a short Plössl,
but how much more you want is not something I know. Other designs can
have "higher" eye relief ranging from around 10mm to 20mm.

By the way, Televues cost as much because they give you well
corrected wide (apparent) fields of view even in fast scopes. In an
f/5.6, you could give the Baader Hyperions a spin, or even one
of the incarnations of the Kunming wide fields (Burgess SWA, Agena
SWA, Orion Q70,...) for the longer focal lengths. They won't be as
good as Naglers in an f/5.6, but they'll cost much less (though I
must confess you'll pry my 26T5 Nagler from my cold, dead fingers).
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