Re: ATM 3" 75mm or 4" 100mm eyepieces

[K1JJ@aol.com]

In a message dated 96-08-19 21:24:08 EDT, you write:

>
>I'm not sure exactly why you would want that long a focal length.  But the
>design objectives for a scope are different than for an eyepiece ... in
>short, scopes are designed with a long focal length and good correction over
>a FOV of a fraction of a degree;  eyepieces are the converse ... short focal
>length and good correction over a wide field of view. You might start by
>looking at copier lenses that require a wide flat field of view ... Joe
>Sunseri had some of Zeiss mnfr at Riverside this year that were 80mm (I
>bought one ... great optics).  
>
>

Hi Chris,



I'm curious what is the barrel or clear aperature diameter of those 80mm
eyepieces? 

T.C.