Re: New AP scope and more

From: Bill McHale (wmchal1_at_alumni.umbc.edu)
Date: 10/30/04 

Date: Sat, 30 Oct 2004 04:05:46 +0000 (UTC)

Chris.B <chris.b@mail.dk> wrote:
: RichA <none@none.com> wrote in message news:<0o93o0lpqmpugv1h4g3a1el1j4e8lorv5b@4ax.com>...
:
:> More than that, why invest such an amount when you could buy
:> a 20" mirror for the same price, with near perfect performance?
:> -Rich

: Are you serious? ;-)

: Assuming you make it a long focus job to avoid coma there's the sheer
: effort in handling such a brute alone. Even if it was an ultralight
: Dob.

Ummm.. with respect, I think if you were to compare a 20" Dob on an ultra
light mounting you would find that it is not nearly as hard to manage as
you might think. Certainly it would be easier than a 9" f/9 refractor and
the equatorial mount and field tripod that would necessary to support such
a big OTA at a decent height. I know our club 17.5" will fit in the back
seat of my VW Jetta; I would like to see the 9" f/9 fit in there. Mind
you I love Refractors, and wouldn't trade my AP130 for any scope, but I
think Apos make more sense in smaller sizes.

: Put a 20" in an observatory and you'd want decent tracking. Think of
: the size of the equatorial mounting and the accomodation necessary for
: your 20" compared with any AP refractor. Not to mention the "fun" of
: balancing on a tall ladder in the dark.

Umm... you don't need an Equatorial mounting for tracking any more. Alot
of Dobs use computerized tracking and if you want astro-photographic
capabilities that can include field de-rotation. 

--
Bill

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