RE: [APML] Four Schmidt Shooters

["Loke Tan" <tan@cox.net>]

Kent,

 When I look at the 14" Schmidt camera, I get the impression that a lot of
the issues with it might come from using a separate guidescope for guiding.
The invar cage appears very rigid but I suspect the whole connection between
the large tube and the invar cage. Maybe one way is to use a very light
guidescope such as the e-finder/STV combo, i.e. something which will not add
in weight and cause flexure relative to the invar cage. Of course one must
get the focus correct as well. The camera is also a two man hoisting job. I
could not do it myself, well not easily at least.
 Another issue with the camera is the lack of a medium format roll film
holder. If you can build one, it will make shooting numerous exposures
relatively easy, and you would also not have to deal with processing film
chips which is a small nightmare as well.

Loke



> -----Original Message-----
> From: astro-photo-bounces@seds.org
> [mailto:astro-photo-bounces@seds.org]On Behalf Of KGKIRKLEY@aol.com
> Sent: Friday, May 30, 2003 8:37 PM
> To: astro-photo@seds.org
> Subject: Re: [APML] Four Schmidt Shooters
>
>
>
> In a message dated 5/30/03 10:11:04 PM, tan@cox.net writes:
>
> >Kent,
> >
> > Here is the picture Andreas sent me:
> >
> >http://starryscapes.com/tmp/C14SC1.JPG
> >
> >I looked up his email and he did say he had two 14" Schmidts from
> >Vehrenberg. Whether it's the two 14" Schmidts in this picture, I do not
> >know. I believe I was told I could pick either one. I did not think it
> >mattered <g>. I was hoping to get the one which was in better
> focus though.
> >Needless to say the one I got is very well focused but for a camera with
> >this speed it will have to be perfect and it's not. I just did not have
> >the
> >time to do it properly, especially since I am not experienced in this.
> >My 8"
> >Schmidt was focused by Epoch.
> >
> >Loke
>
> Loke:
> Yes, precise focus (as well as collimation) is a necessity.
> Of the three sizes of Schmidt cameras that Celestron built, the
> 14 inch was
> the most prone to focus 'instability', mainly because it was a
> large instrument
> and not as rigid as the smaller Schmidt's.
> I saw that you are considering parting with it. Joseph Sylvan is
> doing the
> same thing.
> He began the process of restoration and had the tube repainted
> the original
> Celestron 'Orange but put it up for sale about six months ago. I
> don't know if
> he has found a purchaser.
> Kent Kirkley
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