In a message dated 1/19/2007 7:18:11 AM Central Standard Time,
astronomy@... writes:

Do you know, what is the maximum capacity of 900GTO for
astrophotography? Can I even dream of having 12.5" RCOS on 900GTO?

Certainly!

Roland Christen

Hi,

Do you know, what is the maximum capacity of 900GTO for
astrophotography? Can I even dream of having 12.5" RCOS on 900GTO?

-Pete

In a message dated 1/19/2007 11:52:05 AM Central Standard Time,
bengoshi@... writes:

The same also applies to the 900 QMD?

Jon L. Williams

If you will be doing advanced astrophotography using precision CCD cameras,
then I would recomend the latest servo drive mountings for best results.
Capacity wise, all 900 mounts are the same, but control wise, the servo drives are
the way to go.

Rolando

Should not be a problem. If you go to the RCOS web site and look
under mountings they state the 900 goto will handle the 10 and 12.5
inch RC. The wieght stated for the tube version of the 12.5 inch RCOS
is 48 lbs. figure an extra 20 lbs for camera, adapters, guidescope
and your still within the max loads of the 900 goto.

I've had my 900 goto since October of 1998 and never have run into a
load condition that would be a problem for this mount. My 900 handles
my AP 10 inch Mak Cass with no difficulty. There are people who use a
Celestron 14 with their 900 goto's and claim no difficulties at all.

Clear Skies
Dwight L Bogan

The same also applies to the 900 QMD?

Jon L. Williams

Geometry seems to count as much as weight for mount capacity - my
guess is that a folded scope like the RCOS would be fine, I believe
because the tube length is not that big in comparision to some other
designs.

I've been using a 16" f4.5 on my AP900:

http://santangeli.net/calstar2006/

It's ultralight for the aperture (62lbs including camera), and
probably the absolute max the mount can do, more because of the big
moment arm the OTA creates than the weight.

I'd be curious what AP's thinking was in stating the capacity of
70lbs... 70lbs refractor? Folded scope?

Pete