SkyQuest XT Intelliscopes

Has anyone in the group have experience using the new digital Dobs by Orion?
How do they compare to similar versions of Celestron and Meades GOTO models?

TIA

Steve wrote:
Has anyone in the group have experience using the new digital Dobs by Orion?
How do they compare to similar versions of Celestron and Meades GOTO models?


The GOTO scopes are motorized.

The Dobs just have digitized setting circles and are "PUSHTO" designs.
the DSCs tell you when you have pushed to the right orientation.

The GOTO scopes track. The Dobs do not (no "whining" motors).

The similarities with the LX-200 and NexStar lines are pretty limited.

IMHO Orion's advertizing in the catalog is a bit misleading to a beginner.

Phil

Someone else will have to address that. But the optical concept and
design of an SCT is quite different than a Newtonian .. with pros and cons.

Phil

Steve wrote:
I was aware that you have to "hand move" them to the arrows on the object
controller. I was just curious about the optics of the 10" compared to
similar meade and celestron models.


"Phil Wheeler" wrote in message
...

Steve wrote:

Has anyone in the group have experience using the new digital Dobs by

Orion?

How do they compare to similar versions of Celestron and Meades GOTO

models?

The GOTO scopes are motorized.

The Dobs just have digitized setting circles and are "PUSHTO" designs.
the DSCs tell you when you have pushed to the right orientation.

The GOTO scopes track. The Dobs do not (no "whining" motors).

The similarities with the LX-200 and NexStar lines are pretty limited.

IMHO Orion's advertizing in the catalog is a bit misleading to a beginner.

Phil

"Steve" wrote in message
news:E%u5b.345282$Ho3.50172@sccrnsc03...
I was aware that you have to "hand move" them to the arrows on the object
controller. I was just curious about the optics of the 10" compared to
similar meade and celestron models.


I've owned an 8" Discovery Dob and sold it. Biggest mistake of my
astro-life. I have found that both 8" SCT optics and 8" Discovery (Dob)
Optics to be quite good.

However, I have found that Dobs tend to give brighter images due to fewer
optical surfaces (i.e. no diagonal mirror and no corrector plate as in an
SCT). Plus Dobs have smaller secondary mirrors (which is of lessor impact).

Many in this group will disagree with me, however.

On Thu, 04 Sep 2003 00:46:32 GMT, "Jim" wrote:

I've owned an 8" Discovery Dob and sold it. Biggest mistake of my
astro-life. I have found that both 8" SCT optics and 8" Discovery (Dob)
Optics to be quite good.

However, I have found that Dobs tend to give brighter images due to fewer
optical surfaces (i.e. no diagonal mirror and no corrector plate as in an
SCT). Plus Dobs have smaller secondary mirrors (which is of lessor impact).

Many in this group will disagree with me, however.


So Jim why was the dob a mistake?

Selling the Dob was the mistake.


"Geoff" wrote in message
...
On Thu, 04 Sep 2003 00:46:32 GMT, "Jim" wrote:

I've owned an 8" Discovery Dob and sold it. Biggest mistake of my
astro-life. I have found that both 8" SCT optics and 8" Discovery (Dob)
Optics to be quite good.

However, I have found that Dobs tend to give brighter images due to fewer
optical surfaces (i.e. no diagonal mirror and no corrector plate as in an
SCT). Plus Dobs have smaller secondary mirrors (which is of lessor
impact).

Many in this group will disagree with me, however.


So Jim why was the dob a mistake?

I read it as selling the Dob was a mistake.

Phil

Geoff wrote:
On Thu, 04 Sep 2003 00:46:32 GMT, "Jim" wrote:


I've owned an 8" Discovery Dob and sold it. Biggest mistake of my
astro-life. I have found that both 8" SCT optics and 8" Discovery (Dob)
Optics to be quite good.

However, I have found that Dobs tend to give brighter images due to fewer
optical surfaces (i.e. no diagonal mirror and no corrector plate as in an
SCT). Plus Dobs have smaller secondary mirrors (which is of lessor impact).

Many in this group will disagree with me, however.



So Jim why was the dob a mistake?

Has anyone in the group have experience using the new digital Dobs by Orion?
How do they compare to similar versions of Celestron and Meades GOTO models?

TIA

Which scopes are you comparing them to? The GOTO SCTs? The Newtonians of
various types that Meade and Celestron sell?

jon

"Steve" wrote in message
.net...
Has anyone in the group have experience using the new digital Dobs by
Orion?
How do they compare to similar versions of Celestron and Meades GOTO
models?

Comparing a Celestron 8" SCT with Starbright, to an XT10 Skyquest from Orion
(the older Guan Sheng model). The 10" is brighter, provides better
resolution, and has better response to low contrast details on Mars and
Jupiter. That said, the difference in each case is really marginal, and more
dependent on atmospheric conditions than scope specs and design. When
atmospheric conditions are good for observing, both scopes perform
admirably. The one place where I've seen the XT10 provide an appreciable
improvement, is in drawing out spiral structure in M51 under my local
conditions, as well as allowing easier detection of other objects with low
surface brightness (such as M101). But that's simply a result that a 10"
aperture of any other design would also provide.

Based on the comparison of these two scopes, I would venture a reasonable
guess that a 10" SCT would outperform an 8" F6 Newtonian in brightness and
contrast, and that an 11" SCT would beat a 10" Newt in brightness and
contrast, by a nose. (I'm not promoting one over the other on optics, btw.
As far as I'm concerned, the choice between an SCT and a Newt or Dob of
similar aperture should be made on a combination of things including mount,
portability and versatility. Buying an 8" Newt OTA strictly to outperform an
8" SCT optically is, IMO, unreasonable considering the minimal differences.)

That said, you _will_ need a little more aperture in the SCT, to compensate
for the loss of light on each surface, and to make up for the larger CO. But
again, we're really splitting hairs.

As for the difference between a GoTo and DSCs, I prefer DSCs and an EQ
mounting. They are virtually noiseless, and for visual use provide every bit
the needed accuracy. Add an EQ Platform to a Dob, use a GEM for a Newt or
SCT, or a Fork/Wedge for an SCT, and you have all the function of a GoTo.
There's really only one place where the GoTo is of unquestionable value to
the visual astronomer (although being this is saa, someone will no doubt
object), and that's with an altazimuth fork or Dob mount, since motorized
tracking is then possible.

If you are seriously considering the Dob, buy it because you want a Dob, not
because of any techno gadgets that apply. You will still have to hand-track
using the Dob with DSCs, and tracking is a much larger issue than finding,
IMO.

IOW, based on my current exeperiences with Dobs, Forks, Wedges and GEMs,
given the choice between a Dob with DSCs and a Dob with EQ platform. I'd
definitely go for the one with platform drive. Finding stuff is a pain, but
no where near as much a pain as hand tracking easy to find targets above
some threshold of magnification (in my case, I get annoyed above 150x).
Lastly, with the platform drive, you don't lose your position if you need to
spend time studying the charts during a star hop. That makes star hopping
less of a pain, thus the DSCs less of an advantage.

Stephen Paul

I think you will need (some or all of which you may already have, or may
come with your scope):

1) a membership in a club
2) a flashlight with a red beam
3) a zero power finder (e.g. Rigel Quickfinder)
4) a planisphere
5) an observing guide of some sort (e.g. "Turn Left at Orion")
6) a collimation tool (e.g. a film canister with holes poked in the top and
bottom)

I wouldn't buy anything else until you get a chance to use the scope. Then,
try out other folk's eyepieces, barlows, etc to see how they work for you in
your scope.

You MUST collimate your scope frequently, and it will probably NOT arrive
collimated. To collimate means to adjust the tilt of the mirrors so that
light is reflected straight into your eye. Instructions on how to collimate
will be included with the scope. Star test it every time out to check its
collimation. We have a friend with an Orion 8" dob who collimates it
regularly, and the views through his scope are very nice. Once well
collimated, it only takes a minute to tweak it. The folks in your club will
help you to get the hang of it, and it soon becomes second nature.

Dennis

"riff" wrote in message
news:5hH5b.44656$xf.5448@lakeread06...

"Phil Wheeler" wrote in message
...
Steve wrote:
Has anyone in the group have experience using the new digital Dobs by
Orion?
How do they compare to similar versions of Celestron and Meades GOTO
models?
snip
IMHO Orion's advertizing in the catalog is a bit misleading to a
beginner.


Hi all. I'm a complete "noob" to astronomy and just ordered an 8" dob
from
Orion. I have to agree that the advert copy was misleading to me in that
respect and was glad to see you mention it here Phil. I added the optional
controller because of the wife sigh and would have prefered to spend the
extra bucks on other accessories but look forward to it helping us along a
bit. I figured out that it was really DSC from reading the newsgroups.
One
of the descriptions reads: "Want to view the Whirlpool Galaxy? Press the
button labeled 'Messier' ... select M51 ... whoosh! Wow! In seconds,
there
it is, dead center in the eyepiece." Sounds very much like goto and not
"push-to" although I can see that the intention is that "moi" does the
whooshing. Gotta love those marketing weasels though. ; )

Speaking of accessories for a noob, can any of you experienced observers
suggest starter "must have" accessories? In addition to the padded case
and
controller I added on a 2x barlow. The scope comes with 25.0mm & 10.0mm
eyepieces. My plan is to attend a few local astronomy club skywatch
events
and seek further advice. Any "must have" filters? I apologize for these
very beginner-ish questions. I can see that it would depend upon the
situation but was just curious if there are any items that would be great
to
have in the beginning. Thanks for your advice.

Bob