Re: [APML] Schmidt Camera arrived (finally)

["William R. Mattil" <wrmattil@ix.netcom.com>]

"John C. Mirtle" wrote:
> 
> William;
>     Congrats on getting the Schmidt! Get ready for astrophotography in the
> fast lane. :-) I am all too familiar with that little screw you mention. If
> you look at the base of each spider leg where they join the ring, you will
> find two slotted screw heads and one hole - one per spider vane. The screw
> will most likely be the same size as the other two and fit in the hole. Now
> the bad news. These screws are used to collimate the secondary/film holder.
> Hopefully I am wrong and you have just found a screw used to hold the door
> on, but I have my doubts. I had the same problem, centering the secondary is
> critical but not that difficult.

Hi John,

Thats the screw. In fact :^) one of the others was loose too. The
purpose of these screws is to apprently center the secondary within the
tube and center that part of the optical train with the Primary. I am
guessing that its necessary because the invar rods likely have some flex
to them and the secondary could wiggle a bit. Just because they have
close to zero expansion coefficient doesn't mean that they are rigid :^)

I am really looking forward to this foray into the "fast lane" as you
say. While I don't think it will replace the 10" f/6, 10" f/4 it will
certainly augment them nicely. And I will get to learn some new skill
sets. TechPan, Hypering, developing. This system will also be set up
with my ST-4 because I am having some trouble figuring out how to
interface it to the Parks GEM's. For mounting, it appears that I have a
least two options. They are:


1) Losmandy DSBS, DC14, Parallax rings (mounted just behind the mirror
cell and corrector) And naturally the Guidescope rings on an appropriate
plate,

2) Losmandy DC8, Parallax Rings, DC8 and guidescope rings. This puts the
guidescope on top of the camera and *may* make balancing easier and
requires less outlay of cash :^) which I am short of after funding the
Camera to begin with.

I will need to try an locate a 35 mm film holder to use without a filter
and I suspect that won't be easy. In fact to try and fill this need I
purchased a 5.5" Camera as well but it appeasr that it was/is lost in
shipping and I will never see it. So I still am in need of a film
holder. Perhaps a roll film holder too.

Kent lives a short drive away and I am going to view his setup over the
weekend to try and ascertain the mounting system that I'll use.

Thanks for the kind words. I will certainly let you know how I get on
with this little beastie :^) Think of all the money I'll save on not
buying Eyepieces ! Hows that for rationalization ?


Best Regards

Bill

-- 
William R. Mattil	| Fred Astaire wasn't so great.
wrmattil@ix.netcom.com	| Ginger had to do it all backwards
(972) 399-4106		| and... in high heels.

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