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Equipment Discussions >> ATM, Optics and DIY Forum

Mark Harry
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Reged: 09/05/05
Posts: 3120
Loc: Northeast
Re: How Good a Secondary is needed?
      07/03/09 07:28 AM

My basic rule of thumb, a good smooth 1/8-1/10th surface error; no edge hook. General viewing, it'll kick butt on 99% of what you want to do. Try to keep any variance in the outer 1/4" of the secondary's aperture.
Planetary or other hi-rez/hi-x stuff, get the best you can possibly afford. (big apertures will put you several hundred $ in the hole.)
I tested one of Jay's secondaries when he was having trouble. Pretty sad!
Mark

--------------------
So many projects, so little time!

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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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