Orion Deep Space Explorer
Peter Lill
but before I do I would like to hear about any problems or criticisms anyone
might have with these specific telescopes. Also, how would these telescopes
compare to the Meade Dobsonians or to the newly released Celestron Dobsonians?
P.S.
I have read the reviews in Astronomy Magazine (December, 1993)
Regards:
J.P. Lill
Tom Miller
regularly. My only complaint with these commercial dobs is that they do
not make the altitude bearings large enough to provide adequate friction
control. When you add things like a finder scope or telerad star finder
to the end of the tube, you have to add counter balance weights to the
opposite end of the tube to keep the scope pointed where you want it
without its moving on its own. I put larger bearings on mine from
homemade parts and that helped alot. These scopes are great beginner
scopes and will keep your attention whenever you get them out. Good
luck.
Tom Miller
Cuyahoga Astronomical Association/Cleveland, OH
Tom Picciani
>Regards:
>J.P. Lill
The key problems with the 6 and 8 inch dobs from Orion is that the
mount for the secondary mirror is a stalk and is very hard to
collimate. In these ranges Meade is the better buy IMHO. Once you go
to 10 inches and larger, Orion uses a 4 vane spider and their focal
ratio on the 10 inch is a bit longer allowing for a smaller secondary
mirror and a smaller secondary obstruction giving a bit more contrast.
Don't get the 'extras' package since the eyepieces are junk and the
finder is a toy. Get a Telrad and purchase a good 13mm Teleview
plossl.
You'll need a set of collimation tools but a film canister with a hole
drilled in the back will do in the interum. Get the full set of
Tectron tools when you can afford the $100. Anytime you take the
scope on a trip it's always a good idea to check collimation. For me,
the secondary rarely moves (I check it anyway) but the primary will
usually shift a bit.
Tom P.
Kurt Grosshans
>
>jpl...@pathcom.com (Peter Lill) wrote:
>
>> I am interested in purchasing a 6" or 8" Orion Deep Space Explorer,
>>but before I do I would like to hear about any problems or criticisms
anyone
>>might have with these specific telescopes. Also, how would these
telescopes
>>compare to the Meade Dobsonians or to the newly released Celestron
Dobsonians?
>
>>P.S.
>>I have read the reviews in Astronomy Magazine (December, 1993)
>
>>Regards:
>
>You'll need a set of collimation tools but a film canister with a hole
>drilled in the back will do in the interum. Get the full set of
>Tectron tools when you can afford the $100. Anytime you take the
>scope on a trip it's always a good idea to check collimation. For me,
>the secondary rarely moves (I check it anyway) but the primary will
>usually shift a bit.
>
>Tom P.
This is all excellent advice. However, I would not spend the money on the
collimation devices. Use the "airy disc" method. Sight on a very bright star
(not a planet) and take the image slightly out of focus. You should see a
series of concentric rings surrounding a black spot. The black spot is your
secondary mirror. The black spot should be perfectly centered. If not,
adjust the three screws at the back of the primary until it is. make sure
you keep the airy disc centered in your view.
Good luck.
Jhonny Mnemonic
says...
I'm not sure if you knew, but there is a couterweight kit out there for Dobs
which consists of a velcro strip (which you mount to the top of the tail end
of the tube), and a set of weight bags (filled with sand?) that have velcro
as well, and you use it to balance the scope after adding accessories as you
have described... I think it is a great idea, and I plan to make one myself
when I get a dob scope.
BTW, what exactly can you see through your scope on a good night?...
Andromeda Galaxy? Clusters? Nebula?... how good is the view through the
scope (I am contemplating purchasing one)? Is the supplied eyepeice (26mm
Plossl) a quality one?... and how are the planetary views?
I have a 60mm Bushnell adjustable-zoom scope, and on a good night w/ no wind
I can see the cloud belts on Jupiter, but with much concentration!
I would appreciate if you'd either mail me (cn3...@coastalnet.com), or post
to this group.
Thanks in advance,
eager,
Scott Goodman
cn3...@coastalnet.com
Frizz
cn3...@coastalnet.com (Jhonny Mnemonic) wrote:
>I'm not sure if you knew, but there is a couterweight kit out there for Dobs
>which consists of a velcro strip (which you mount to the top of the tail end
>of the tube), and a set of weight bags (filled with sand?)
^^^^^^^^^^^^^^^^
Metal shot(BBs, maybe). I'd be leery of sand.
The DSE has a threaded hole that you can screw a weight-holder into.
Tech support sez that it can hold up to 5lbs, which is more than
enough. You could screw a hook in to hold small weights to "fine
tune" the balance as you change eyepieces.
I'm using duct tape and large washers on the bottom of the scope on my
DSE. Works fine, so far.
>BTW, what exactly can you see through your scope on a good night?...
>Andromeda Galaxy? Clusters? Nebula?... how good is the view through the
>scope (I am contemplating purchasing one)? Is the supplied eyepeice (26mm
>Plossl) a quality one?... and how are the planetary views?
My 8-inch DSE faintly shows the cloud bands on Saturn (w/7.5mm @ 163x)
if the atmosphere is stable. With the 26mm, Andromeda is clear, and
so are the two companion galaxies. This was in sub-optimal lighting
conditions with non-dark-adapted eyes.
Clusters? Well, I don't get into clusters much.
Nebs? The Orion Neb looks great, particularly at 163x.
=FRIZZ= Member alt.aol-sucks Troll Patrol(tm), Goon Squad Division
Finger for PGP 2.6.2 Public Key. Unsolicited *commercial* email is
subject to download/archival fee of $200 US per message. E-mailing
denotes acceptance of these terms. (My mailbox - a spam free zone!)
David K Martin
: On 31 Jan 1996 02:16:01 GMT, in sci.astro.amateur,
: cn3...@coastalnet.com (Jhonny Mnemonic) wrote:
: >I'm not sure if you knew, but there is a couterweight kit out there for Dobs
: >which consists of a velcro strip (which you mount to the top of the tail end
: >of the tube), and a set of weight bags (filled with sand?)
: ^^^^^^^^^^^^^^^^
: Metal shot(BBs, maybe). I'd be leery of sand.
Its filled with lead shot. I had to remove a pound or so from mine to
get the balance right on my 8" DSE. Before I broke down and bought
Orion's somewhat overpriced kit, I used a cloth coin purse filled with
steel BBs and foam rubber (kept the BBs from shifting) and a couple
large rubber bands to strap it to the tube. The weight bag and velcro
strip do look better and are much more convienent to use.
Dave Martin - d...@col.hp.com
aalexand
> I am interested in purchasing a 6" or 8" Orion Deep Space Explorer,
> I have read the reviews in Astronomy Magazine (December, 1993)
> Regards:
> J.P. Lill
I own an 8" Orion Deep Space Explorer. I have also looked through a 6" DSE.
They are both good scopes with the 6" offering better planet views (had
better corrected optics). The 6" is also easier to carry.
The eyepiece (Sirius 26mm Plossel) is quite good (far better than
Meade's MA series eyepieces).
My 8" DSE had a lot of little defects:
Did not balance with supplied eyepiece and no finder.
focuser was not centered over hole in tube.
secondary mirror was way out of alignment.
center pivot in the base was too tight.
I fixed these problems with out much trouble (I like to mess with
things) and did not deal with Orion's service dept. From what I've
heard, they would have been helpful.
The review in Astronomy was about a previous model. The base is
different (does not come assembled). There are some other differences
that I don't remember.
I have not seen either Meade's or Celestron's dobs. I have seen four
different Meade MA series eyepieces. All except one where rejects due
to imperfections in the lenses or coating. Even when there are no
defects, they have poor eye relief (even the 40mm!), only one surface
anti-reflection coated, and narrow field of view. If you want
inexpensive eyepieces, buy Pro-Optic Plossels from Adorama.
In comparing prices, add the price of an additional eyepiece to Meade's
price as you will be tossing the one they send you.
Hope this helps. Clear skies, Andy
Rocket J. Squirrel
I bought a 10" Deep Space Explorer last year. Full details are on my Web
page at <http://www.radix.net/~ratatosk/>
Clear Skies,
Rocky
--
Rocky (rata...@radix.net>
Tom Picciani
fr...@mont.mindspring.com (Frizz) writes:
>On 31 Jan 1996 02:16:01 GMT, in sci.astro.amateur,
>cn3...@coastalnet.com (Jhonny Mnemonic) wrote:
>
>
>>I'm not sure if you knew, but there is a couterweight kit out there for Dobs
>>which consists of a velcro strip (which you mount to the top of the tail end
>>of the tube), and a set of weight bags (filled with sand?)
> ^^^^^^^^^^^^^^^^
>
>Metal shot(BBs, maybe). I'd be leery of sand.
>
>Tech support sez that it can hold up to 5lbs, which is more than
>enough. You could screw a hook in to hold small weights to "fine
>tune" the balance as you change eyepieces.
>
>I'm using duct tape and large washers on the bottom of the scope on my
>DSE. Works fine, so far.
>
>
>
>>BTW, what exactly can you see through your scope on a good night?...
>>Andromeda Galaxy? Clusters? Nebula?... how good is the view through the
>>scope (I am contemplating purchasing one)? Is the supplied eyepeice (26mm
>>Plossl) a quality one?... and how are the planetary views?
>
>My 8-inch DSE faintly shows the cloud bands on Saturn (w/7.5mm @ 163x)
>if the atmosphere is stable. With the 26mm, Andromeda is clear, and
>so are the two companion galaxies. This was in sub-optimal lighting
>conditions with non-dark-adapted eyes.
>
>Clusters? Well, I don't get into clusters much.
>
>Nebs? The Orion Neb looks great, particularly at 163x.
>
>
>
>=FRIZZ= Member alt.aol-sucks Troll Patrol(tm), Goon Squad Division
>Finger for PGP 2.6.2 Public Key. Unsolicited *commercial* email is
>subject to download/archival fee of $200 US per message. E-mailing
>denotes acceptance of these terms. (My mailbox - a spam free zone!)
loop all the way around. That's one nebula that really comes to life
with the filters.
On my homemade 10 inch f-6.3, a 9 mm Nagler will put me inside M-13
or just about any other globular.
Tom P.
Jon LaCure
>
>My 8" DSE had a lot of little defects:
>Did not balance with supplied eyepiece and no finder.
>focuser was not centered over hole in tube.
>secondary mirror was way out of alignment.
>center pivot in the base was too tight.
>
Hi, I'm struggling with this right now and I wondered if you or
anyone else might have some tips to share. I think I have the
focuser fairly close to squre. I did this by simply tightening
the nuts and bolt, all but one of which were very loose.
The stalk that holds the secondary has been much more
problematic. It was easy enough to bend it so that all of the
image of the primary now appears in the secondary, however the
secondary is not centered under the focuser. It is my
understanding that I'm supposed to see roughly concentric circles
in a sight tube. I can do this with either the secondary mirror
OR the image of the primary, but not with both. While this may
be a simple and straight forward process with a spider, I'm guessing
that with a stalk it is going to require some thoughtful and more
complex bending, perhaps with pliars.
I have the AstroSystems combination Cheshire/Sightube but not the
Autocollimator. Most of the information I have comes from their
booklet which was written for larger and fancier telescopes than
mine.
-- Jon
Jon LaCure
Dept. of Romance and Asian Languages and Literatures
601 McClung Tower / Univ. of Tennessee, Knoxville
Knoxville, TN 37996-0460
John B. Randolph
Explorer by David K Mar...@col.hp.co
> get the balance right on my 8" DSE. Before I broke down and bought
> Orion's somewhat overpriced kit, I used a cloth coin purse filled with
> steel BBs and foam rubber (kept the BBs from shifting) and a couple
> large rubber bands to strap it to the tube. The weight bag and velcro
> strip do look better and are much more convienent to use.
>
> Dave Martin - d...@col.hp.com
What I did was to put a couple of strips of velcro at the base of my
dob and a couple of strips of velcro on a box that I filled with
pennies. It works quite well. A big eyepiece, and I move the box back
toward the end; lighter, forward... Of course, lead shot would mean
a smaller box, but I didn't have any of that lying around...
- John
aalexand
> In article <4et74d$o...@usenet.ucs.indiana.edu>, aale...@ezinfo.ucs.indiana.edu (aalexand) writes...
> >
> >My 8" DSE had a lot of little defects:
> The stalk that holds the secondary has been much more
> problematic. It was easy enough to bend it so that all of the
> image of the primary now appears in the secondary, however the
> secondary is not centered under the focuser. It is my
> understanding that I'm supposed to see roughly concentric circles
> in a sight tube. I can do this with either the secondary mirror
> OR the image of the primary, but not with both. While this may
> be a simple and straight forward process with a spider, I'm guessing
> that with a stalk it is going to require some thoughtful and more
> complex bending, perhaps with pliars.
right.
I bent mine with an end nipper but pliers should work as long as you do
your bending with the stalk unmounted. I was very careful to not let
the tool touch the glass of the mirror. I bent the stalk forward near
the focuser and backward (toward the primary) near the secondary mirror.
The first bend brought the secondary in line with the focuser. The
second bend aligns the image of the primary with the secondary.
Before you bend the secondary, you should center it in the tube, then
adjust the primary to align it with the secondary by looking down the
tube from the front (described in the booklet from Orion). You may have
to do several iterations to get this all correct. I don't have the
AstroSystems stuff.
Good Luck, and clear skies, Andy