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Date: 21 Jul 2006 12:02:17
From: bob
Subject: Celestron flavours
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I'm presently considering a Celestron 9.25" SCT, and am curious about the
practical differences between the Advanced series and the CGE series. The
price difference is huge. I would buy a non-GOTO if I lived in the country,
but it's a huge convenience when you live in a light polluted location. Is
the EQ-5, as found on the Advanced series, the right mount for this scope,
or is it "underpowered", so to speak?
Thanks
--
Bob
Travel and Astronomy Photos
http://www3.sympatico.ca/bomo
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Date: 21 Jul 2006 09:20:18
From: RMOLLISE
Subject: Re: Celestron flavours
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bob wrote:
> I'm presently considering a Celestron 9.25" SCT, and am curious about the
> practical differences between the Advanced series and the CGE series. The
> price difference is huge. I would buy a non-GOTO if I lived in the country,
> but it's a huge convenience when you live in a light polluted location. Is
> the EQ-5, as found on the Advanced series, the right mount for this scope,
> or is it "underpowered", so to speak?
>
Hi:
Me? I'm through buying non-goto scopes. ;-)
As for the CGE vice ASGT, the CGE is a much heavier duty mount, and is
certainly advisable if you're considering heavy imaging, especially
with the C11. OTOH, the ASGT's CG5 works very well...surprisingly well
for the price.
Peace,
Rod Mollise
Author of:
Choosing and Using a Schmidt Cassegrain Telescope
and
The Urban Astronomer's Guide
<http://skywatch.brainiac.com/astroland >
The Annual SCT User Imaging Contest is Underway!
<http://www.rothritter.com/contest/2006/ >
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Date: 21 Jul 2006 12:48:31
From: bob
Subject: Re: Celestron flavours
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"RMOLLISE" <rmollise@hotmail.com > wrote in message
news:1153498816.937805.319260@b28g2000cwb.googlegroups.com...
> Hi:
>
> Me? I'm through buying non-goto scopes. ;-)
Oh no, please don't....!
>
> As for the CGE vice ASGT, the CGE is a much heavier duty mount, and is
> certainly advisable if you're considering heavy imaging, especially
> with the C11. OTOH, the ASGT's CG5 works very well...surprisingly well
> for the price.
>
I do like the solidity of the CGE, and I do need a good mount for
photography, but if I can get away with spending $2000 less for something
almost as good, I'm game. I may see if my local shop has them for rent. For
visual observing, anything will do so long as it tracks in RA and doesn't
wiggle too much when I focus, but I think I'm done with fork mounts.
Thanks
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Date: 21 Jul 2006 14:46:55
From: William Hamblen
Subject: Re: Celestron flavours
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On 2006-07-21, bob <me@here.ca > wrote:
> I'm presently considering a Celestron 9.25" SCT, and am curious about the
> practical differences between the Advanced series and the CGE series. The
> price difference is huge. I would buy a non-GOTO if I lived in the country,
> but it's a huge convenience when you live in a light polluted location. Is
> the EQ-5, as found on the Advanced series, the right mount for this scope,
> or is it "underpowered", so to speak?
I do believe the 9.25" SCT is too large for the EQ-5. I have
put a C8 on an EQ-6 with good results. The 9.25" SCT is about
twice as heavy as a C8, but I think the EQ-6 can handle it.
The next step up would be a Losmandy G-11 or the Celestron
CGE.
Bud
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Date: 21 Jul 2006 15:55:40
From: bob
Subject: Re: Celestron flavours
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That would be disappointing, since Celestron sells the 9.25 on an EQ-5
mount. If the mount is not up to the task, they shouldn't sell it as a
package.
--
Bob
Travel and Astronomy Photos
http://www3.sympatico.ca/bomo
"William Hamblen" <wrhamblen@comcast.net > wrote in message
news:2uGdnd2BFemyslzZnZ2dnUVZ_u-dnZ2d@comcast.com...
> On 2006-07-21, bob <me@here.ca> wrote:
> > I'm presently considering a Celestron 9.25" SCT, and am curious about
the
> > practical differences between the Advanced series and the CGE series.
The
> > price difference is huge. I would buy a non-GOTO if I lived in the
country,
> > but it's a huge convenience when you live in a light polluted location.
Is
> > the EQ-5, as found on the Advanced series, the right mount for this
scope,
> > or is it "underpowered", so to speak?
>
> I do believe the 9.25" SCT is too large for the EQ-5. I have
> put a C8 on an EQ-6 with good results. The 9.25" SCT is about
> twice as heavy as a C8, but I think the EQ-6 can handle it.
> The next step up would be a Losmandy G-11 or the Celestron
> CGE.
>
> Bud
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Date: 21 Jul 2006 19:30:12
From: Stephen Paul
Subject: Re: Celestron flavours
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bob wrote:
> That would be disappointing, since Celestron sells the 9.25 on an EQ-5
> mount. If the mount is not up to the task, they shouldn't sell it as a
> package.
>
>
To put this into perspective, I actually had no major grievances using
the C9.25 on an older Celestron/Vixen GP mount with wood legs and manual
slow motion controls (no motors) for globular and galaxy observing (180x
and 97x). (It was certainly easier to carry out fully assembled than
with the AS-CG5.)
Now consider that the AS series CG5 is more robust than the old, tried
and true Vixen GP. It's plenty enough mount for the C9.25 for visual
deep sky use.
For planets it would be nice to have a motorized focuser for powers over
200x to reduce vibrations while critical focusing, but that's almost
always true without _over-mounting_ any scope.
I also had the C9.25 up on a G11 and it was rock solid (aka over mounted
for visual, and well matched for imaging).
The C11 on the other hand is certainly over the limit for sensible use
on the AS-CG5, except maybe at low powers.
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Date: 21 Jul 2006 17:46:54
From: William Hamblen
Subject: Re: Celestron flavours
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On 2006-07-21, bob <me@here.ca > wrote:
> That would be disappointing, since Celestron sells the 9.25 on an EQ-5
> mount. If the mount is not up to the task, they shouldn't sell it as a
> package.
That never stopped them before.
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Date: 21 Jul 2006 20:41:44
From: Roger Hamlett
Subject: Re: Celestron flavours
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"bob" <me@here.ca > wrote in message
news:AO-dnQyqi6PZrFzZnZ2dnUVZ_vOdnZ2d@giganews.com...
> That would be disappointing, since Celestron sells the 9.25 on an EQ-5
> mount. If the mount is not up to the task, they shouldn't sell it as a
> package.
> --
> Bob
It is OK, for _visual_ use, but for imaging, is 'undermounted'. The same
is true of the C11 (which weighs about the same), and the C10 NGT.
The current ASGT mount, performs very well for the money, but you do not
get a good heavy duty imaging mount for this sort of money...
The latter tripod, and improvement in the gears on this mount, make it one
of the best 'value' mounts around.
Best Wishes
> Travel and Astronomy Photos
> http://www3.sympatico.ca/bomo
>
>
>
>
> "William Hamblen" <wrhamblen@comcast.net> wrote in message
> news:2uGdnd2BFemyslzZnZ2dnUVZ_u-dnZ2d@comcast.com...
>> On 2006-07-21, bob <me@here.ca> wrote:
>> > I'm presently considering a Celestron 9.25" SCT, and am curious about
> the
>> > practical differences between the Advanced series and the CGE series.
> The
>> > price difference is huge. I would buy a non-GOTO if I lived in the
> country,
>> > but it's a huge convenience when you live in a light polluted
>> > location.
> Is
>> > the EQ-5, as found on the Advanced series, the right mount for this
> scope,
>> > or is it "underpowered", so to speak?
>>
>> I do believe the 9.25" SCT is too large for the EQ-5. I have
>> put a C8 on an EQ-6 with good results. The 9.25" SCT is about
>> twice as heavy as a C8, but I think the EQ-6 can handle it.
>> The next step up would be a Losmandy G-11 or the Celestron
>> CGE.
>>
>> Bud
>
>
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Date: 22 Jul 2006 17:31:31
From: Al
Subject: Re: Celestron flavours
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"bob" wrote in message news:AO-dnQyqi6PZrFzZnZ2dnUVZ_vOdnZ2d@giganews.com...
> That would be disappointing, since Celestron sells the 9.25 on an EQ-5
> mount. If the mount is not up to the task, they shouldn't sell it as a
> package.
Hi Bob,
IMHO the EQ5 mount is adequate (at least for my Celestron 8" Newt) for
visual work only. Admittedly the longer tube of the Newt makes harder work
for the mount but 8" Newt vs 9.25 SC would have (ballpark) similar inertia.
HOWEVER- the trap NOT to fall into (and I did) is to get the EQ5 and then
retro-fit Celestron's dual- (or single-) axis motor drive. This option
seemed attractive to me, but the build quality of the retro-fit is woeful. I
can't say this too many times or loudly enough. When the retro-fit kit
arrived I attempted to fit as per the (somewhat brief) instructions. Some
gear parts were so inaccurately machined that they simply would not line up.
I wasted far too much time sourcing other shims and washers etc to get the
parts aligned. Once lined up, the periodic error is enough to make even
low-powered visual use somewhat frustrating, and high-powered views give
stars appearing and disappearing like yo-yos. Photographic work is
impossible. The hand-controller also had a fault - the Northern/Southern
hemisphere slide switch would only maintain contact once it was taped into
position. I sent this part back to my supplier who kept it for 8 weeks then
sent it back (unchanged). (This is a local distributor gripe - *not* a
Celestron gripe, but the switch problem should not have made it past quality
control).
I have since discarded this kit, and the mount now serves in the original
unaltered mode as a reasonable hand-guided EQ5. It is very stable (if a
little heavy), and vibration damping is very reasonable (and I don't use
vibration suppression pads, although I hear of many who swear by them).
Good luck with your purchase.
Al
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Date: 22 Jul 2006 11:56:18
From: bob
Subject: Re: Celestron flavours
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Well, these are exactly the sorts of input I was looking for, and thanks. It
makes sense that the EQ-5 is probably adequate as a visual mount for the
9.25 scope, and I suspect it would suit me fine if that was my only use. I
want to do more imaging, and although it would probably "work", I'd like
something more solid than my current fork mount/wedge situation. I suppose a
better, after-market wedge is a possibility too, but I prefer an EQ mount,
and who could argue against another 1.25" of aperture?
--
Bob
Travel and Astronomy Photos
http://www3.sympatico.ca/bomo
"Al" <null@null.com > wrote in message
news:44c1d45d$0$25358$afc38c87@news.optusnet.com.au...
>
> "bob" wrote in message
> news:AO-dnQyqi6PZrFzZnZ2dnUVZ_vOdnZ2d@giganews.com...
>> That would be disappointing, since Celestron sells the 9.25 on an EQ-5
>> mount. If the mount is not up to the task, they shouldn't sell it as a
>> package.
>
>
> Hi Bob,
>
> IMHO the EQ5 mount is adequate (at least for my Celestron 8" Newt) for
> visual work only. Admittedly the longer tube of the Newt makes harder work
> for the mount but 8" Newt vs 9.25 SC would have (ballpark) similar
> inertia.
>
> HOWEVER- the trap NOT to fall into (and I did) is to get the EQ5 and then
> retro-fit Celestron's dual- (or single-) axis motor drive. This option
> seemed attractive to me, but the build quality of the retro-fit is woeful.
> I can't say this too many times or loudly enough. When the retro-fit kit
> arrived I attempted to fit as per the (somewhat brief) instructions. Some
> gear parts were so inaccurately machined that they simply would not line
> up. I wasted far too much time sourcing other shims and washers etc to get
> the parts aligned. Once lined up, the periodic error is enough to make
> even low-powered visual use somewhat frustrating, and high-powered views
> give stars appearing and disappearing like yo-yos. Photographic work is
> impossible. The hand-controller also had a fault - the Northern/Southern
> hemisphere slide switch would only maintain contact once it was taped into
> position. I sent this part back to my supplier who kept it for 8 weeks
> then sent it back (unchanged). (This is a local distributor gripe - *not*
> a Celestron gripe, but the switch problem should not have made it past
> quality control).
>
> I have since discarded this kit, and the mount now serves in the original
> unaltered mode as a reasonable hand-guided EQ5. It is very stable (if a
> little heavy), and vibration damping is very reasonable (and I don't use
> vibration suppression pads, although I hear of many who swear by them).
>
> Good luck with your purchase.
>
> Al
>
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Date: 21 Jul 2006 13:00:41
From: Stephen Paul
Subject: Re: Celestron flavours
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bob wrote:
> I'm presently considering a Celestron 9.25" SCT, and am curious about the
> practical differences between the Advanced series and the CGE series. The
> price difference is huge. I would buy a non-GOTO if I lived in the country,
> but it's a huge convenience when you live in a light polluted location. Is
> the EQ-5, as found on the Advanced series, the right mount for this scope,
> or is it "underpowered", so to speak?
>
> Thanks
>
>
For visual use the Advanced Series GT-C9.25 works just fine (I had one).
That said, EQ mounts are really only beneficial (required) for imaging.
If you have NO intentions whatsoever in getting into imaging, it might
make more sense to look at a CPC-925 for convenience and ease of setup
(has no counterweights, requires no polar alignment, just a tripod and a
fork mount, no need to be able to even see the celestial pole).
With _that_ said, the AS-CG5-GT mount is capable of imaging with a 6" F5
Newt or an 80mm F7.5 (Orion 80ED) refractor and a DSLR (two relatively
inexpensive ways to experiment). So, if you go with the C9.25 on the
AS-GT mount, you can use it for imaging with smaller scopes. That's not
something that you can do with the fork, without a wedge and a piggy
back arrangement, which gets costly in a hurry.
Good luck.
Stephen Paul
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Date: 22 Jul 2006 07:50:13
From: RMOLLISE
Subject: Re: Celestron flavours
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> I do believe the 9.25" SCT is too large for the EQ-5. I have
> put a C8 on an EQ-6 with good results. The 9.25" SCT is about
> twice as heavy as a C8, but I think the EQ-6 can handle it.
> The next step up would be a Losmandy G-11 or the Celestron
> CGE.
Hi:
It depends on what your use for the scope is. The 9.25 (or the 11) on
the CG5 is perfectly OK for casual imaging and visual use. 6 hour long
LRGB exposures? That might be a wee bit much (but people have done
that...the mount autoguides well).
Peace,
Rod Mollise
Author of:
Choosing and Using a Schmidt Cassegrain Telescope
and
The Urban Astronomer's Guide
<http://skywatch.brainiac.com/astroland >
The Annual SCT User Imaging Contest is Underway!
<http://www.rothritter.com/contest/2006/ >
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