Re: Use of stereo eyepieces in compound microscope???

Flourite objectives are sometimes called semi-apochromats. These use
Flourite lens elements in designs related to achromats (in terms of
the number and placelment of lens enelments) to obtain much better
color correction.  

Aaron

On Sun, 23 Nov 2003 20:32:59 GMT, "Kevin Cunningham"
<[EMAIL PROTECTED]> wrote:

>
>"BOB MARABLE" <[EMAIL PROTECTED]> wrote in message
>news:[EMAIL PROTECTED]
>> I'm just a hobbiest at microscopy, with a very limited "allowance" for
>> equipment (hope my wife doesn't read this!) Here's my problem--I have
>> a Zeiss Axiostar 'scope, with infinity tube correction, and which
>> takes the larger-size 30mm barrel eyepieces.  New eyepieces of this
>> size are very expensive, and I've found only a meager market for used
>> items for this series--however, I think many stereo 'scopes use 30mm
>> eyepieces, and there's substantial availability of used and
>> alternative-vendor items for these 'scopes.  What are the
>> issues/ramifications of using "stereo scope" eyepieces in a compound,
>> infinity system?? I appreciate all input!!
>> Bob Marable
>
>I wouldn't recommend using a stereo eyepiece at all.  The first point is
>that your Zeiss is infinity corrected, the beam path from the objective to
>the eyepiece is parallel.  This is not the case with some stereos so the
>microscope will not produce the correct power and corrections such as
>parfocality.  It' just better to find some eyepieces designed for this
>instrument.  A minor point,sleeves to adapt regular eyepieces to larger size
>openings can be had for free or very little, Olympus among others gave them
>away.  Oh, I have never heard of a "semi-apo".  Maybe I'm confused.
>
>Kevin
>