Re: 8" Newtonian choice

Later I picked up an Advanced Series CG-5GT and transplanted the 2"
steel
leg tripod and the GoTo system to the GP head. This made the setup with
the
Konus 200F5 a _lot_ more stable. So I can say with some confidence that
the
Celestron 8" F5 on the Advanced Series mount is stable enough, and the
others (Konus and Orion) are not, not really. Not without that 2"
'steel leg
tripod.
---------

Stephen:

I also have a Konus 200mm F5 on the CG5ASGT and my experiences mirror
yours. It works, it is stable enough but it is awkward and given the
choice between my 10 inch DOB and the EQ mounted Konus, it's the DOB
every time. In the 4 or 5 months I have had the ASGT mount I have used
it twice, once to see how the GOTO worked and the other time to see how
it worked without the GOTO. It is currently scheduled to move over to
my nephews house, he likes gizmos and gadgets.

One problem with using a Newtonian on a GOTO EQ mount is that you
really need "rotating rings." Moving from one part of the sky to
another with an EQ mounted Newt requires repositioning the OTA in the
rings. However one has to be careful not to loosen the rings too much
or the tube will slip down. So, leaving the rings tight enough to
prevent the tube from slipping down opens the door to the possibility
to slipping the clutches and having to start over on the alignment.

These days I have been enjoying some of the older style EQ mounts for
Newts, the Criterion RV-6 mount and the Meade Research Grade with the
12.5 inch F6 OTA. These have slip clutches built into the RA drives
and using them is much like using a DOB, you just point em and where
ever you stop, the scope tracks. No fumbling in the dark for those
levers that somehow always disappear. Of course these are not as free
from vibration as a DOB mount and the larger one means most viewing
will be done on a ladder but the simplicity and ease of pointing in
addition to the tracking made them an interesting option.

But in the end, as Stephen Paul says, it is a DOB that comes out most
evenings. I say give a DOB a try, some folks are reluctant at first to
give them a try. I know thought DOBs were a crude, not worthy of the
name telescope. But after having seen one in action and then buying a
used 8 incher I came to the believe that DOBs are a tour de force in
Elegent Simplicity, a clear design that just works.

jon...

.

Relevant Pages

  • Re: 8" Newtonian choice
    ... > leg tripod and the GoTo system to the GP head. ... > choice between my 10 inch DOB and the EQ mounted Konus, ... In the 4 or 5 months I have had the ASGT mount I have used ... > really need "rotating rings." ...
    (sci.astro.amateur)
  • Re: star hopping [Ammendment]
    ... there are two very positive cases for GoTo. ... > mount that could automatically slew to an object. ... cool a larger scope. ... The 12.5" Dob is nice for sure, but frankly I'd rather have the 3" smaller ...
    (sci.astro.amateur)
  • Re: Opinion on Questar telescopes
    ... well with a simple Dob mount. ... I have carried a 6-inch collapsible Newtonian on a plane, ... I typically observe planets at 300x or higher with medium to large ... Following a planet with a well-made Dob isn't nearly as hard as some ...
    (sci.astro.amateur)
  • Re: Does the ETX 70 AT share the same mount as the ETX 90?
    ... >I eventually plan to get an inexpensive DOB... ... The fork is make of tiny plastic parts held together by small self tapping ... tiny dots or maybe tiny disks, just a tad larger than the distorted stars. ... I was never able to enjoy its goto capabilities, ...
    (sci.astro.amateur)
  • Re: Get Me Started (again...)
    ... It looks like I'm going with either a DOB or a Newt on a EQ mount. ... The only reason I'm after the mount is for tracking - I really want to be able to track an object without having to re-center every minute or so. ... I'll live without goto, but I've got to find the best atlas I can get, so I'll be able to find things. ...
    (sci.astro.amateur)