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Equipment Discussions >> ATM, Optics and DIY Forum
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Houdini
professor emeritus


Reged: 07/13/07
Posts: 523
Loc: Europe
Re: How Good a Secondary is needed?
      07/03/09 06:19 AM
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Quote:

Agree - without posting up a bunch of supporting ZEMAX analysis and/or quoting Suiter, I can tell you with certainty that diagonal curvature more than 1/10 wave P-V is enough to generate astigmatism at high powers.


Please do post a couple of ZEMAX analyses, I don't accept your certainty without proof .

Robert

--------------------
16" f/4.9 motorized alt-az, 25" f/5 Dobson, 43" f/4 alt-az under construction
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Entire thread
Subject Posted by Posted on
* How Good a Secondary is needed? gaz-in 07/02/09 04:49 PM
. * Re: How Good a Secondary is needed? Mike I. JonesModerator   07/03/09 11:00 AM
. * Re: How Good a Secondary is needed? Mark Harry   07/03/09 01:09 PM
. * Re: How Good a Secondary is needed? gaz-in   07/03/09 12:01 PM
. * Re: How Good a Secondary is needed? bbasiaga   07/02/09 05:02 PM
. * Re: How Good a Secondary is needed? llanitedave   07/02/09 06:40 PM
. * Re: How Good a Secondary is needed? Bird   07/02/09 09:41 PM
. * Re: How Good a Secondary is needed? Mike I. JonesModerator   07/02/09 10:13 PM
. * Re: How Good a Secondary is needed? Houdini   07/03/09 06:19 AM
. * Re: How Good a Secondary is needed? Mike I. JonesModerator   07/03/09 08:14 AM
. * Re: How Good a Secondary is needed? Houdini   07/03/09 08:42 AM
. * Re: How Good a Secondary is needed? jayscheuerle   07/03/09 10:52 AM
. * Re: How Good a Secondary is needed? Mark Harry   07/03/09 07:28 AM
. * Re: How Good a Secondary is needed? Mark Harry   07/03/09 07:34 AM
. * Re: How Good a Secondary is needed? walt r   07/02/09 11:55 PM

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