Re: [ATM] Testing a Scope. i'm astigmatic and myopic

[Charles Broward <cbroward@ufl.edu>]

Hi Ian,
I too have astig....makes it frustrating to see if scope is good or not!

Try moving around the ep and seeing if the X rotates with your 
eye...also see what the intra and extra focus images look like.  If you 
are using a diagonal rotate it....

I bought a Dioptrix astig compensator gizmo at the WSP and finally have 
star images that look like points instead of little comets!

I could, prior to the Dioptrix,  take a eyeglass lens and hold it close 
to the ep and correct a fair amount of astig...but that is unwieldy.

I used to think all my scopes were bad....

Chuck in N. Florida

Ian McKernan wrote:
> Hmm, if this is inappropos say, but i am after info on a star test of a little 130mm Mak Cass. I have read up that the out of focus image being different inside and out of focus is not an issue like it is for a newt.  However, even when i was testing my first mirror i knew i was always going to see some astigmatism since i am short sighted and astigmatic. I tend to observe with my glasses off since most of my eyepieces re not the best for eye-relief.
>
> The query is that the in focus images at 200x magnification show the stars as crosses?? Anyone have any ideas as to whether this is the scope or my astigmatism??  No surgery has been done, and the myopia is compensated by focusing.  Any opinions welcomed!
>
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-- 
-------------------------
Chuck  Broward
WretchedSky Observatory
Melrose, Florida
352-475-1014
cbroward@ufl.edu
www.afn.org/~broward




-- 
-------------------------
Chuck  Broward
WretchedSky Observatory
Melrose, Florida
352-475-1014
cbroward@ufl.edu
www.afn.org/~broward

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