That's good material, Chip. My Orion prism is a very good performer. Thanks.
Bill


----- Original Message -----
From: Chip Zempel <czempel@...>
To: <80f5@onelist.com>
Sent: Tuesday, September 14, 1999 6:19 PM
Subject: [80f5] Prism vs. Mirror diagonals


> From: Chip Zempel <czempel@...>
>
> The Orion Short Tube 80 comes with a 45 degree correct-image diagonal,
> that's intended for terrestrial viewing. (Some of the other variations of
> this scope may also - I'm not sure.) Replacing this with a 90 degree star
> diagonal is probably the single most significant improvement you can make
> on the performance of this scope for astronomical viewing.
>
> But the question is: should I buy a mirror diagonal or prism diagonal?
>
> I did a little research (mainly by using DejaNews to read through old
> newsgroup postings in sci.astro.amateur and emailing Orion's technical
> support). Here is a summary of the main arguments, as I understand them.
> (Please feel free to emend or amend):
>
> --------- Mirror diagonals ---------
> Pros: Higher contrast than prism diagonals. Enhanced coatings have
> highest reflectivity. Because these tend to be about twice as expensive
> as prism diagonals, no one makes low quality ones. (In other words, why
> make a cheapo mirror diagonal when someone looking to save money will buy
> a prism?) Adjusting collimation may be easier (especially on some models)
> but that may also imply that going out of collimation may be easier, too.
>
> Cons: Fragile. Coatings lose reflectivity over time (years?). Standard
> coatings are not as reflective as high-quality prisms.
>
> --------- Prism diagonals ---------
> Pros: Less expensive. Better reflectivity than standard coatings on
> mirror diagonals. Less fragile. Name-brand diagonals should be of good
> quality, though there are a lot of "department store" scopes with
> no-name, inferior prism diagonals on them. Less fragile.
>
> Cons: Light must travel through two glass surfaces, reducing contrast.
> Difficult to collimate, if out of collimation. Not as reflective as
> enhanced coating mirror diagonals.
>
> --------- My conclusions (your mileage may vary) --------
> For my Orion ST80, the customer/tech support person I had email contact
> with at Orion suggested I get the prism diagonal. I'm glad I did. Here
> was my (our) reasoning:
>
> 1) This is supposed to be a rich-field scope. The extra contrast of a
> mirror diagonal might be nice for planetary/lunar viewing, but for faint
> fuzzies and star fields, it's not as important.
>
> 2) The prism apparently has better reflectivity than the standard-coating
> mirrors. At first, a prism has less reflectivity than enhanced-coating
> mirrors, but they degrade over time. Prisms don't deteriorate. The
> standard coating diagonals start out worse than prisms, and then get more
> worse. (Worser worse?)
>
> 3) I'm cheap. Instead of a Lumicon enhanced diagonal (about $100), I got
> an Orion prism diagonal ($36 on sale last spring) with enough money left
> over for a UO Orthoscopic eyepiece.
>
> 4) I'm clumsy, especially in the dark. 'Nuff said?
>
> (Comments from others are encouraged!)
>
> Chip Zempel
> czempel@...
>
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37 and counting. I have noticed a disturbing trend. Very few of the 37 are
galaxies. Hopefully, there is not a brick out there waiting for me.
Bill

----- Original Message -----
From: <RMOLLISE@...>
To: <80f5@onelist.com>
Sent: Tuesday, September 14, 1999 7:53 PM
Subject: Re: [80f5] test/hello everyone


> From: RMOLLISE@...
>
> In a message dated 9/14/99 6:17:25 PM Central Daylight Time, rde@...
> writes:
>
> << At the moment, I'm about 25 M-objects into the Messier list; I also
>  use the scope on the Moon, Jupiter, and Saturn.  Usual observing sites
are
>  from the Ile d'Orleans and Rawdon, Quebec. >>
>
> Hi Roderick:
>
> That's my goal as well..do the full Messier with Little 80...
>
> After the Messier...well if J.R. Freeman can do the Herschel 400 with
> Refractor Red what's to stop me from doing it with Little Bird 80?! Oughta
be
> a CINCH!!  :-)
>
> Peace,
> Rod
>
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In a message dated 9/14/99 6:17:25 PM Central Daylight Time, rde@...
writes:

<< At the moment, I'm about 25 M-objects into the Messier list; I also
  use the scope on the Moon, Jupiter, and Saturn.  Usual observing sites are
  from the Ile d'Orleans and Rawdon, Quebec. >>

Hi Roderick:

That's my goal as well..do the full Messier with Little 80...

After the Messier...well if J.R. Freeman can do the Herschel 400 with
Refractor Red what's to stop me from doing it with Little Bird 80?! Oughta be
a CINCH!!  :-)

Peace,
Rod

Some time ago, I received some suggestions for fixing up my Orion ST80
from Bob Berta, and I thought I would pass them along to this list.
(Sorry for redundancy if they've already been posted. I just subscribed.)
(And thanks, Bob, if you're reading this!)

1) Loosening the retaining ring on the objective lens. It seems almost
all of these scopes were shipped with pinched optics. How tight should it
be? Mine is tight enough that the lens assembly doesn't rattle when you
shake the scope, but loose enough that if you give the side of the scope
a sharp *rap*, you can hear the lens ass'y shift inside the tube.

2) Removing the lens assembly and painting the edges of the lenses black.
This helps reduce internal reflections and improve contrast. Be sure to
keep the lenses together in the proper orientation and put them back in
the right way! I just used a black Magic Marker (TM) to blacken the
edges.

3) Take the slack out of the focusing tube. I tried this and wasn't too
successful. I just read Dave Randell's suggestion of swapping the two
screws (I didn't realize they were different!) and I'll see if this
helps.

4) Look inside the tube for any screw heads, and paint any that you find
with flat black paint. I didn't have any black paint handy the night I
took the scope apart, so I didn't bother with this one. They're way down
inside the tube and well out of the light path, so I didn't bother. But
I'll try it sometime.

5) Replace the 45 degree diagonal with a 90 degree star diagonal. WOW!
Did this ever make a difference! Prism or mirror? I called Orion, and
they suggested that I buy a prism diagonal rather than a mirror diagonal,
so that's what I got. (And I saved enough money to buy a UO Orthoscopic
eyepiece!) I'll post more about diagonals in a separate note.

Of course, your mileage may vary. Please be careful, especially if you're
removing lenses, etc!

Chip Zempel
czempel@...

The Orion Short Tube 80 comes with a 45 degree correct-image diagonal,
that's intended for terrestrial viewing. (Some of the other variations of
this scope may also - I'm not sure.) Replacing this with a 90 degree star
diagonal is probably the single most significant improvement you can make
on the performance of this scope for astronomical viewing.

But the question is: should I buy a mirror diagonal or prism diagonal?

I did a little research (mainly by using DejaNews to read through old
newsgroup postings in sci.astro.amateur and emailing Orion's technical
support). Here is a summary of the main arguments, as I understand them.
(Please feel free to emend or amend):

--------- Mirror diagonals ---------
Pros: Higher contrast than prism diagonals. Enhanced coatings have
highest reflectivity. Because these tend to be about twice as expensive
as prism diagonals, no one makes low quality ones. (In other words, why
make a cheapo mirror diagonal when someone looking to save money will buy
a prism?) Adjusting collimation may be easier (especially on some models)
but that may also imply that going out of collimation may be easier, too.

Cons: Fragile. Coatings lose reflectivity over time (years?). Standard
coatings are not as reflective as high-quality prisms.

--------- Prism diagonals ---------
Pros: Less expensive. Better reflectivity than standard coatings on
mirror diagonals. Less fragile. Name-brand diagonals should be of good
quality, though there are a lot of "department store" scopes with
no-name, inferior prism diagonals on them. Less fragile.

Cons: Light must travel through two glass surfaces, reducing contrast.
Difficult to collimate, if out of collimation. Not as reflective as
enhanced coating mirror diagonals.

--------- My conclusions (your mileage may vary) --------
For my Orion ST80, the customer/tech support person I had email contact
with at Orion suggested I get the prism diagonal. I'm glad I did. Here
was my (our) reasoning:

1) This is supposed to be a rich-field scope. The extra contrast of a
mirror diagonal might be nice for planetary/lunar viewing, but for faint
fuzzies and star fields, it's not as important.

2) The prism apparently has better reflectivity than the standard-coating
mirrors. At first, a prism has less reflectivity than enhanced-coating
mirrors, but they degrade over time. Prisms don't deteriorate. The
standard coating diagonals start out worse than prisms, and then get more
worse. (Worser worse?)

3) I'm cheap. Instead of a Lumicon enhanced diagonal (about $100), I got
an Orion prism diagonal ($36 on sale last spring) with enough money left
over for a UO Orthoscopic eyepiece.

4) I'm clumsy, especially in the dark. 'Nuff said?

(Comments from others are encouraged!)

Chip Zempel
czempel@...

Gordon Hengst <GrantGGH@...> wrote:

>I own the Orion ST 80 but I need some suggestions for a medium weight
>tripod as my Velbon Tripod DH-20/4 is too light weight (2.3 lbs.)  If I so
>much as breathe on it, it shakes worse the 1989 Loma Prieta Earthquake.
>Also, the 3-way pan head isn’t strong enough to hold the Short Tube very
>well. I bought an Orion Precision Slow-Motion Adapter and it made things
>easier to track but it doesn’t help with the shakes. I would especially
>like to hear from owners of Bogen/Manfrotto tripods as to what tripod and
>head combinations that they are using. I own the SkyView Deluxe EQ Mount
>but it’s too big to use for a quick set-up and peek type of thing.

I have a Star-D camera tripod that is incredibly sturdy, even when fully
extended. This is a professional photographer's tripod (but not a studio tripod,
it's more portable than those monsters). It's light and relatively small when
folded up. There's an almost identical model in the current Porter's Camera
catalog - Tiltall Pro TE-01B. Porter's item no. 16-0214. Six pounds, extends to
70 inches, 30 inches closed. $146.95 (ouch - we got ours for $79 twenty years
ago!)

My only complaint is that it's not quite as smooth as I would like in the
altitude direction. A little too loose, and the scope slips, a little to tight
and it binds and then overshoots. But I haven't really tried to tinker with
this. I'm sure I could make it better, but it's not too much of a problem. With
your Slo-Mo adapter, that shouldn't be a problem anyway.

Porters can be reached at http://www.porters.com/ or 800-221-5329. I've never
ordered from them, so I can't make a recommendation one way or another. Don't
know how complete their web site is, either.

Chip Zempel
czempel@...

Dave-

Thanks for the tips! I especially like the idea of rotating the finder so
the crosshairs are at 45 degrees. I never would have thought of that, and
yet when you mention it, it's SO obvious! (Yes, I use mine on an alt-az
mount!)

I'm not sure yet that I'm ready yet to try messing with my collimation
(and at 80X max with my current setup, I'm not sure I really need to!),
but I appreciate all the pointers.

The objective end of my Orion ST80 seems quite a bit different from your
scope. Mine is an early model, bought shortly after they first came out.

Dave Randell <ff77@...> wrote:

>1 Collimation and testing
>I found my scope came with the objective screwed down far too tight in the
>cell, and was out of collimation.  An initial star test showed a
>distinctive triangular shape (pinched optics) to the Airy pattern either
>side of focus.  This was easily resolved: you just need to gently remove
>the dew cap (it just slides off)

The dew cap on my (early production run) Orion ST 80 _screws_ on. A bit
confusing - sometimes it's hard to tell if you're unscrewing the dew cap
from the objective or the objective from the tube. Be careful!

>1.1 Adjustment of the cell
>With the dew cap removed you will see three (otherwise hidden) screws that
>hold the cell to the tube.  If you slacken these off, you will find that
>you now have some lateral movement to play with; its a question of
>squaring on then re-tightening.
>

Same thing, again. My objective assembly _screws_ onto the tube, ie, the
inside of the tube is threaded and the outside of the objective is
threaded and they screw together. The dew cap screws _onto_ the objective
cell, and that screws _into_ the tube. In other words, the tube and dew
cap both have female threads, the objective cell has male threads on both
ends. (My focuser has three screws as Dave described, however.)

Chip Zempel
czempel@...

test


	 Hello all.  I see a lot of the usual suspects from s.a.a. here...


	 I am the proud owner (for about eighteen months) of a Vista 508
(the dark blue Canadian version).  I keep it mounted on a second-hand GEM
that used to support a 4.5" Bushnell newt.  I use it with 20mm, 12.5mm, and
1.5 mm Omcon plossls and an Antares barlow.

	 At the moment, I'm about 25 M-objects into the Messier list; I also
use the scope on the Moon, Jupiter, and Saturn.  Usual observing sites are
from the Ile d'Orleans and Rawdon, Quebec.

	 I don't get out enough these because a) I live in an apartment now
and b) have a pretty time-consuming job.  Last year, I was living in a
house in the burbs, and so used the scope for grab&go.  However, its
portability is still really handy now that I have to travel to get to my
observation sites.

	 Anyhow, glad to see the list up and running!




Roderick Darroch Elliott <rde@...>

I love this story. Not long ago, our little astronomy club went tripping out to
our dark sky site for an evening of observing. I zipped on out there with
you-know-who tucked beneath my arm. Some of the telescopes there were a tad
larger than the ShortTube 80. An 18" DOB, a 12.5" DOB and other instruments of
more modest dimensions. It gets better. The owner of the 12.5" DOB (an extremely
nice guy) came drifting over to look at my scope. He was quite taken with the
appearance of the ST80. Then he paused. "You know", he said, "That looks a lot
like the finder scope on my DOB. My God. It IS the finder scope". It's good we
were out in the country and well away from polite society. We were all laughing
like lunatics (a subtle astro reference there). The little runt was the center
of attention and he handled it well.
Much later I was looking at M27. After much fiddling, I had, with the help of a
broadband filter, a really nice image. The big DOB owner came by again and this
time wanted to see what I was looking at. He took a peek. A long peek. He said,
quite seriously, "I had no idea it could do that". Was I smiling? Take a guess.

Bill

Hi,
It is not exactly clear to me where this is going - the entire mailing list?

Diagonals: The Orion prism diagonal seems quite good to me. I've been
pleased with the performance.

Eyepieces: Higher powers in these little lads is tricky. The UO Orthoscopics
work very well. Very crisp. If you wear glasses (I do), they are great for
planetary observing but the limited eye relief and field of view make them
less desirable for other types of viewing. I have a 7mm and a 5mm.
On paper, the Vixen Lanthanums sound promising but do not perform as well as
the Orthos in this fast little refractor. In my f/8 refractor, the
Lanthanums really hit their stride. I know you don't want to drop a bundle
on an eyepiece and I certainly understand. These little scopes really seem
to like good eyepieces. My 7mm Pentax works great. Of course, the eyepiece
costs more than the scope. It does give one pause, I must say. Another
approach is to consider a stronger barlow. I have a Klee 2.8x and it
performs very well in the f/5 refractor. It allows you to use a lower focal
length eyepiece and still get some reasonable power while retaining decent
eye relief.
Bill


----- Original Message -----
From: <RMOLLISE@...>
To: <sct-user@egroups.com>; <80f5@onelist.com>
Sent: Tuesday, September 14, 1999 7:58 AM
Subject: [80f5] Re: [sct-user] Diagonals


> From: RMOLLISE@...
>
> In a message dated 99-09-14 08:32:48 EDT, you write:
>
> <<
>  In anticipation of the arrival of my Eagle Optics 80EQ WA and keeping in
>  mind that I can't afford a Lumicon just now, what do folks recommend as a
>  decent, affordable, replacement diagonal?  Are the ones that Orion sells
>  okay?  In the short run, I'll probably just use the diagonal from my LX10
>  but I'd like to have a spare for those times I want to set up both
scopes.
>
>  Also, what would be a good, short fl, high power eyepiece (again keeping
in
>  mind that I can't manage a Nagler just now)?  The highest power eyepiece
I
>  have right now is the Meade SP4000 9.7mm but I'd like to pick up
something
>  in the 5-7mm range.
>   >>
>
> Hi Ray:
>
> In my experience, the Orions are fine, as are the Meades. _Anything would
be
> better than the included diagonal_. At least if they're all as bad as the
one
> I received. I tested it in the 80 last night by trading it in an out with
a 5
> year old Celestron prism diagonal. Results? Not only was the 'good'
Celestron
> much sharper, but also more color free (don't ask me why). With the prism
> diagonal in place, Altair looked as perfect as perfect could be at 120x.
> Sharp, airy disk and diffraction rings perfect. In went the included
mirror
> diagonal (which despite having a plastic housing, looked pretty good).
With
> the stock diagonal, Altair suddenly grew a prominent purple halo.
Diffraction
> rings were also less well defined.
>
> Cheap, good, highpower eyepieces? I vote for Orthoscopics, and especially
> University Optics Orthos. If you can put up with their relatively small
> apparent fields of view, these oculars will really please.
>
> Peace,
> Rod
>
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In a message dated 99-09-14 08:32:48 EDT, you write:

<<
  In anticipation of the arrival of my Eagle Optics 80EQ WA and keeping in
  mind that I can't afford a Lumicon just now, what do folks recommend as a
  decent, affordable, replacement diagonal?  Are the ones that Orion sells
  okay?  In the short run, I'll probably just use the diagonal from my LX10
  but I'd like to have a spare for those times I want to set up both scopes.

  Also, what would be a good, short fl, high power eyepiece (again keeping in
  mind that I can't manage a Nagler just now)?  The highest power eyepiece I
  have right now is the Meade SP4000 9.7mm but I'd like to pick up something
  in the 5-7mm range.
   >>

Hi Ray:

In my experience, the Orions are fine, as are the Meades. _Anything would be
better than the included diagonal_. At least if they're all as bad as the one
I received. I tested it in the 80 last night by trading it in an out with a 5
year old Celestron prism diagonal. Results? Not only was the 'good' Celestron
much sharper, but also more color free (don't ask me why). With the prism
diagonal in place, Altair looked as perfect as perfect could be at 120x.
Sharp, airy disk and diffraction rings perfect. In went the included mirror
diagonal (which despite having a plastic housing, looked pretty good). With
the stock diagonal, Altair suddenly grew a prominent purple halo. Diffraction
rings were also less well defined.

Cheap, good, highpower eyepieces? I vote for Orthoscopics, and especially
University Optics Orthos. If you can put up with their relatively small
apparent fields of view, these oculars will really please.

Peace,
Rod

Hi,
I have a couple of Bogen tripods and heads. The slickest arrangement is, of
course, the most expensive. As a general note, I almost always observe
sitting down. This is the result of being, from birth, a lazy slug.

Bogen 3021 tripod with 410 (3270) geared head. The 3021 is way more tripod
than is needed. The 3011 would be a better choice and it is still pretty
close to overkill. The 410 Head is geared with slo-mo controls. Extremely
solid and easy to use. But the head is expensive (about $140.00 or so).
Therefore this combination is recommended with reservations. I also have a
pair of semi-large binoculars (11x70s) which I can use with this setup.
Since the 410 head uses quick release mounting plates, I can switch between
the ST80 and the binoculars in a few seconds. Since I have more than one use
for this combination, the cost does not bother me (much). If my only purpose
was to mount the ST80, other combinations make more sense.

Bogen 3001 tripod with 3126 video pan head. This is a really light tripod.
When I received it, I was afraid that it would be too wimpy for even the
ST80 but I was wrong. A slightly heavier tripod such as the 3011 would seem
more solid and might be preferred for that reason alone. The 3126 head does
not have a quick release plate. The 3130 is essentially the same head with
the quick release plate but in some ways it may not be as good. The 3126 is
around $50-55. It is good piece of gear. It has pan bar (handle) that is
very useful. One of the strong points of the 3126 is that the mounting plate
is a bit longer than many - just under 4 inches. This plate has a long slot
(about 3 inches) in it that permits you to position the scope fore or aft
and therefore achieve better balance. The tricky part of using the head is
moving the scope in altitude. Since the head is not geared, friction is used
to hold the head (and scope) in any given position. Too little tension and
you have floppiness, too much and you have difficulty moving it at all. But
it is better than it sounds. It takes some practice, but this little head
can be quite effective. It seems to work best as a two-handed operation -
one hand on the handle & the other to control the friction on altitude. It
is not as clumsy as it sounds. The more you use it, the more intuitive it
becomes. Of course, it is what we use in actual practice that counts. If I
wish to zip over to a nearby soccer field to get an open look at the
southern sky, I don't even think about it. The 3001 tripod, 3126 head, ST80,
a couple of barlows and eyepieces and I am gone. I have the Orion case for
the ST80 which holds the scope, finder scope, diagonal and an eyepiece. That
goes over my sloping shoulder, the tripod in the same hand and the
eyepieces/barlows stuffed in a cheap little hunting vest from WalMart.
Rather sounds like a recommendation does it not? It is.

Bogen does have a site on the web. www.bogenphoto.com/
You may request literature online and they will send it quite quickly. Very
nice brochures with all the specs. for their equipment.

Bill

----- Original Message -----
From: <GrantGGH@...>
To: <80f5@onelist.com>
Sent: Monday, September 13, 1999 12:08 PM
Subject: [80f5] 80f5 Tripod and Head suggestions


> From: GrantGGH@...
>
> Hi gang:
>
> I own the Orion ST 80 but I need some suggestions for a medium weight
tripod as my Velbon Tripod DH-20/4 is too light weight (2.3 lbs.)  If I so
much as breathe on it, it shakes worse the 1989 Loma Prieta Earthquake.
Also, the 3-way pan head isn't strong enough to hold the Short Tube very
well. I bought an Orion Precision Slow-Motion Adapter and it made things
easier to track but it doesn't help with the shakes. I would especially like
to hear from owners of Bogen/Manfrotto tripods as to what tripod and head
combinations that they are using. I own the SkyView Deluxe EQ Mount but it's
too big to use for a quick set-up and peek type of thing.
>
> Best Regards,
> Gordon Hengst
> PS - Thanks to Dave Randell for his wonderful posting on tips for
improvement.
>
>
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>   http://www.onelist.com/community/80f5

In a message dated 99-09-13 12:11:08 EDT, you write:

<< There's also a sweet spot in the center of the focal plane
  where abberations are almost non-exsistant. With the total weight
  of about 5 or 6 pounds it got me a much needed astro fix. This
  setup is pretty stable when the tripod in not extended. The
  mount's movements are chunky but usable. It's great to be able
  to toss this setup outside for a quick ahhhh and hit the sack
  with a smile.
   >>


Hi Frez:

Yep, tell me about it! And yes, I've also discovered that at a certain
position in the field, spurious color basically disappears (not too bad on
Jupiter, anyway).

Peace,
Rod

In a message dated 9/13/1999 1:08:44 PM Eastern Daylight Time,
GrantGGH@... writes:

> Subj:  [80f5] 80f5 Tripod and Head suggestions
>  Date:    9/13/1999 1:08:44 PM Eastern Daylight Time
>  From:    GrantGGH@...
>  Reply-to:    <A HREF="mailto:80f5@onelist.com">80f5@onelist.com</A>
>  To:  80f5@onelist.com
>
>  From: GrantGGH@...
>
>  Hi gang:
>
>  I own the Orion ST 80 but I need some suggestions for a medium weight
tripod
> as my Velbon Tripod DH-20/4 is too light weight (2.3 lbs.)  If I so much as
> breathe on it, it shakes worse the 1989 Loma Prieta Earthquake. Also, the 3-
> way pan head isn’t strong enough to hold the Short Tube very well. I bought
> an Orion Precision Slow-Motion Adapter and it made things easier to track
but
> it doesn’t help with the shakes. I would especially like to hear from
owners
> of Bogen/Manfrotto tripods as to what tripod and head combinations that
they
> are using. I own the SkyView Deluxe EQ Mount but it’s too big to use for a
> quick set-up and peek type of thing.
>
>  Best Regards,
>  Gordon Hengst

    I have the bogen 3001 tripod, and stroboframe ball head. although I dont
have
   my scope yet, I have used it and the 3021 bogen and several gitzo tripods in
   the past doing lots of photography with long lenses 300 f2.8, 400 f3.5, etc.
   in the 6 pound range. The gitzos are smooth steady and pricey. the bogen
   3021 will work with a 10 pound load, the 3001 will do about 6 pounds well,
it
   does depend on the head. I have both catalogs in front of me if you need
more
   info.tripod leg weights follow: 3001=3.8 lbs,3021=5.75lbs.

Hi gang:

I own the Orion ST 80 but I need some suggestions for a medium weight tripod as
my Velbon Tripod DH-20/4 is too light weight (2.3 lbs.)  If I so much as breathe
on it, it shakes worse the 1989 Loma Prieta Earthquake. Also, the 3-way pan head
isn’t strong enough to hold the Short Tube very well. I bought an Orion
Precision Slow-Motion Adapter and it made things easier to track but it doesn’t
help with the shakes. I would especially like to hear from owners of
Bogen/Manfrotto tripods as to what tripod and head combinations that they are
using. I own the SkyView Deluxe EQ Mount but it’s too big to use for a quick
set-up and peek type of thing.

Best Regards,
Gordon Hengst
PS – Thanks to Dave Randell for his wonderful posting on tips for improvement.

Hey Guys:

Just found out about the 80mm short tube list and had to sign up.  I bought
the Eagle Optics/Celestron version back in February as a compliment to my
less-than-portable Losmandy G-11 mounted C8.

It certainly is a great performer for the money.  A couple of weekends ago I
took it up to my parents' place where, with the aid of darker skies and a
Lumicon UHC filter, I was able to tease out the North American nebula.  I
used my 35mm Ultima to bag it - it filled the FOV nicely.  I'd never seen
this nebula "live" before, it was much more sharply defined than I thought
it would be.  I've never attempted to find it with my C8, as I'd heard it's
just too big and spread out for that scope.

Anyhow, I'm glad this list is up and running, and I look forward to sharing
info on this great little 'scope!

--Dave O'Toole
   odave@...
   http://www.concentric.net/~odave

Hi everyone
After working 16 hours and getting home at 3:30 AM, my
local skies were spotless and I was dead tired. The 8" SCT
sat pleadingly next to the door, but wasn't even considered.
SkyView mounts are far from heavy. In my state it might as
well have weighed 100 lbs. Time for option 3. I put the 80f5
on my cheapo Vivitar V3000 Walmart special. With scope mounted
and EPs in the other hand it was a lightweight trip outdoors.
Extending this tripod to full height is silly at best, but
making a second trip for a chair wasn't gonna happen. After
focusing on Jupiter the image shook like 200 flies on a cow flop
for about 4 seconds. Still I managed to enjoy Jup/Sat and M42
for about 20 minutes at 15,32,64 & 84x. Using a 1.25 extension
tube allows my Meade 140 barlow to be used in front of the diagonal.
With a Meade 3000 9.5mm this gives 126x. Very nice. Has anyone
noticed that higher powers seem to reduce chromatisism with these
scopes? There's also a sweet spot in the center of the focal plane
where abberations are almost non-exsistant. With the total weight
of about 5 or 6 pounds it got me a much needed astro fix. This
setup is pretty stable when the tripod in not extended. The
mount's movements are chunky but usable. It's great to be able
to toss this setup outside for a quick ahhhh and hit the sack
with a smile.

Best to all
Frez

Hi everybody,

Here's a copy of the original posting I made to s.a.a.  Don't be put off trying
out these improvements - can make a lot of difference...

Regards,
Dave Randell

P.S. Anybody else having a problem trying to format text to only 80 characters
per line or thereabouts on this group?

------------
80mm f/5 refractors - tips for improvement

As there are a lot of 80mm f/5 scopes out there I thought I'd post the following
to this group.  In my case, I have a Konus Vista-80; but as far as I can tell
the Orion Short Tube, and the other 80mm f/5 scopes currently available, all
stem from the same root.  So on that assumption, the following should apply:

1 Collimation and testing
I found my scope came with the objective screwed down far too tight in the cell,
and was out of collimation.  An initial star test showed a distinctive
triangular shape (pinched optics) to the Airy pattern either side of focus. 
This was easily resolved: you just need to gently remove the dew cap (it just
slides off) and then look at the outer retaining ring that holds the objective
in situ.  Just unscrew and ease this off a little; usually all you need is for
the objective to be gently held, that's all.  However, you may find, as I did,
that despite this remedial action, the objective is too tight on the diameter. 
I found by removing the objective completely, and turning it around in the cell
until it seated better, a slight trace of on-axis astigmatism (remaining from my
initial attempts at re-collimation) was subsequently cured.  If this still fails
to ease the tightness, then one may need to skim the inside of the cell using a
metalworker's lathe.

As for collimation, this can be fiddly, but is worth the effort. There are three
lines of attack: (i) adjustment of the cell; (ii) adjustment of the focusser
unit held in the tube, and (iii) adjustment of the focusser tube with respect to
the focusser unit.  I'll deal with each case in turn:

1.1 Adjustment of the cell
With the dew cap removed you will see three (otherwise hidden) screws that hold
the cell to the tube.  If you slacken these off, you will find that you now have
some lateral movement to play with; its a question of squaring on then
re-tightening.

1.2  Adjustment of the focusser unit
Adjustment of the focusser unit: as above, three (visible) screws to slacken off
and re-tighten yielding some lateral movement.

1.3  Adjustment of the focusser tube
The focusser tube is held securely in place by an internal strip of what looks
like white teflon.  This is pushed down on top of the tube with compensating
pressure pushing up from the r&p unit.  In my case the focusser tube was tilted
up too much, i.e. the geometrical axis of the focusser tube was intersecting the
objective at a point above centre.

I disassembled the unit and removed the two small grub screws that are used to
both hold the teflon strip in situ in the unit and apply pressure to the top of
the tube itself.  The two grub screws used in my unit are different - one is
pointed, the other not.  The pointed one is used to apply pressure to, but also
helps keep, the strip in place as the tube moves back and forth when you focus. 
The other simply applies pressure on the tube.  In my case the flat bottomed
grub screw was at the eyepiece end, and when tightening this it was contributing
to the tilt of the tube.  So I removed the screws and switched them around to
reverse the tilt, or at least mitigate its effects.  However, before I did this,
I also tightened up the four screws holding the r&p unit before I tightened the
two grub screws down.

2  Star testing and collimation
I star tested the scope to collimate as well as check out the optics.  I used an
artifical star while going through the mechanical adjustments described above
using a torch placed at no more than 15 feet away from the scope.  At this close
distance spherical aberration (overcorrection) is introduced into the wavefront,
so one cannot draw much in the way of conclusions of certain lens aberrations,
but for collimation its fine, as all one needs to see is the Airy disc and rings
and their concentricity.  So importing spherical aberration into the image is
not a problem.

I used a 5mm eyepiece (80X) and this eyepiece with a 3X barlow (240X).  Coarse
adjustment was made using the lower power, then fine tuning as best I could do
with the eyepiece/barlow combination.  You might find it useful to defocus until
you see a crimson red spot in the centre of the defocussed Airy pattern as part
of this process, as the centrality of this seemed particularly sensitive to
errors in collimation.

The end result was a pretty well defined Airy disc and first ring.  Originally I
had a a tad of astigmatism - visible only by seeing four small indents in the
first ring, but even this was eventually cleared up by turning the objective in
its cell.  Using the torch was also useful for looking at the iterative effect
of collimation on an extended image, as even a slight improvement in the
collimation seemed to show up as a improvement of the image at 240X, and
vice-versa.

3  The 1/4-20 threaded bush
Mine has a plastic boss with a 1/4-20 threaded insert used to attach the scope
to a tripod.  Don't tighten this up too much or you may split this - mine does
not seat well enough on the tube for that.  In fact I removed mine altogether,
and used a pair of plastic 3" diameter downpipe brackets I got from a builders
merchant.  These open to 90mm and cradles the tube.  I then removed and glued
the brass 1/4-20 threaded insert into a wooden base, and then screwed the two
feet of the two pipe brackets to this.  Its pretty secure.  Total cost 1.60
pounds sterling.  One can of course get a pair of Vixen rings and bracket that
allows one to mount the OTA on a photographic tripod, but for visual use, the
plastic rings suit my needs.

4  The 6X30 finder
The 6X30 finder supplied with my scope turned out to be a 6X24 finder.  The
finder has a diaphragm or stop positioned between the objective and eyepiece
that was vignetting the light cone - in my scope it was positioned about 40mm
down the tube.  This stop can be safely removed by unscrewing the objective cell
where it can be accessed and hooked out.  The fit is resonably tight, but by
moving the stop side to side it can be 'walked' up the tube and removed.  The
colour correction of the objective does not seem to suffer from this remedial
action, one iota.

If the scope is used on a simple alt-az mount, rotate the finder until the
cross-hair is turned through 45 degrees with respect to the vertical.  The
cross-hair is pretty thick, and easily hides some target star.  By orienting the
reticle in this manner, and moving the scope either in altitude or in azimuth,
its much easier to see when a star is central and not hidden by the cross-hair. 
In other words one can easily see where the star is while moving the scope in
either axis - and only disappears when precisely on the intersection - which is
what you want.

If you have a Vixen SP/GP mount don't forget the clip-on polar scope
illuminator.  This clips over the objective end of the finder - so you can have
an illuminated finder reticle too.

5) The 45-degree prism diagonal
On some scopes, e.g the Konus Vista-80 and the Orion Short Tube, the scope comes
with a 45-degree prism diagonal as standard.  The 45 degree prism diagonal is
fine for terrestial viewing, but for astronomical subjects the 90-degree prism
diagonal is a much better option in my opinion; not just in terms of the viewing
angle, but also because the 45-degree diagonal vignettes the apparent field of
some longer focal length eyepieces.  The point is simply this: if you want to
get the maximum true field this scope is capable of returning, then you simply
cannot achieve it using the 45-degree diagonal.

6) Out in the field
Here's some idea of what all this activity resulted in.  In general, I now find
I can regularly take the scope up to 162X with no visible sign of degraded
images.  At even higher magnifications Vega at 240X now shows a clean Airy disc
and complete first and fainter second ring - in fact the amount of impedimeta in
the image was surprisingly little.  On test double stars: Epsilon Lyra (the
double-double) now splits into its four components at 80X and above, with Airy
rings visible too.  Epsilon Bootes also resolves, with the bluish comes emerging
out of the first ring.  Xi Uma resolves too (which being close to 1.5
arcseconds) shows the scope is performing to Dawes limit for the aperture. 
Jupiter sports numerous bands, and Saturn has shown banding on the planet, and
shadowing cast by the ring system clearly visible on the ball of the globe.

When it comes down to it an 80mm f/5 scope is hardly intended to be used as
anything other than a rich-field telescope; however, its intensively satisfying
to find the scope capable of withstanding high magnifications too.

Dave Randell

Hi Gang:

The skies were not perfect last night, but I did get out with my little C80WA
last night for an hour or so.

Earlier in the day I'd finished adjusting the RA worm on the little German
mount. It needs to be _just right_. Too tight against the gear and the RA
slow motion will bind. Too loose and RA slow motion becomes sloppy with lots
of backlash. With the gear overly loose, a small turn of the control will
occasionally send an object at high power right out of the field (with the
target coasting and continuing to move after you stop turning the slow motion
control). In this smallGEM design (which has been around forever in small
imported mounts), the worm engaging the RA gear also provides stability. If
the worm is too loose against the gear, the mount will develop play in its RA
axis. Nevertheless, a few minutes with the mount, a ratchet set and a cup of
coffee were sufficient for me to get things close to 'just right.'

As I trotted the scope outside. I was again struck by how nice it is to
travel light --once in a while, anyway. The scope, a couple of eyepieces, an
Orion "Deepmap" and a miniature version of David Chandler's planisphere could
be carried in one trip. Amazing!  There's somethign to be said for
minimalist/QRP astronomy! This being a work night (I have to get up and 5:25
every morning), Jupiter and Saturn were out of the question. That left double
stars and deep sky objects. In additon to living in the _extremely_ light
polluted historic Garden District in Mobile, I also have the area's prime
attraction (in addition to the Victorian/Ante-bellum homes), towering oak
trees to contend with. The 80 is really proving its worth here. I can trot it
around the yard to take advantage of the few open spaces available to me.

Being in the clear, Beta Cygni was an obvious and beautiful target! I never
tire of looking at this golden/sapphire duo! And the C80WA didn't disappoint!
Colors were beautiful and the pair displayed nice airy disks/diffraction
patterns at 116x. I stared at the pair for quite a while, using a variety of
powers to admire their majesty. Again I was struck by how nice a combination
the scope and mount make. Without being too heavy, it's nice and stable. More
stable, IMHO, than Celestron's other popular refractor/mount the C102 and CG4
mount.

What else to see? Not much around tonight. Oh, M15 was lurking in the east,
but it was in the midst of a light-pollution 'enhanced' layer of haze/fog
growing in that direction. But I wanted to try my small wonder on a real deep
sky object. Well, M57, near the zenith, couldn't be much better placed.
Headed over that way. Located the position in the finder (my little 30mm
finder's nice and bright, by the way), and then refined my position with the
main/scope 25mm SMA combo. Being able to use such a wide field for object
location was a pleasant experience, for sure. In the right place, and able to
make out a wee and fuzzy star which I knew was M57, I went to higher power,
57x, using a 7mm Orthoscopic. There it was, faint, but unmistakable.
Hmmm..since it was looking this good, I wondered what an OIII filter might do
on this little telescope (OIIIs usually seem at their best with larger
apertures). In it went. Nice job. M57 with the help of the OIII revealed
itself as a little smoke ring (no, I DIDN'T see the central star).  I stuck
with the object for quite a while, trying a variety of eyepieces. With the
tripod fully extended and the C80WA pointed near zenith, the eyepiece was at
just the right height for comfortable viewing while seated in a handy lawn
chair. When I pulled my eye away from the eyepiece, though, it was clear that
the conditions had degraded further. I was also being eaten by Asian Tiger
Mosquitoes, despite having sprayed myself with OFF (be very careful with DEET
repellents around scopes). How about one more?

Not too much left (ironically, when I got up at 5:20am, the sky was
beautiful...no doubt it cleared shortly after I shut down!). Well, there's
always the Double/Double. With the seeing as good as it was, and diffraction
patterns in view for the stars, I figured it wouldn't be much of a challenge,
but it is always a treat. It was obviously split at 57x, but 120x provided a
more pleasing view. All four stars were eensy beensy little specks of fire
and were clearly and nicely split.

Interesting if short evening...I'll be out there again tonight if the sky
gods cooperate.

Peace,
Rod

Hi,
Is there a way we could gather up the various little tips that folks know of for
improving our little guys? Back in April, Robert Berta posted some of these tips
and they were very helpful (I saved the post). The one that was of most value to
me was the way in which slack could be removed from the focuser. The focuser
went from OK to very good in mere moments.
Thanks
Bill

YES!

-----Original Message-----
From: robmurr@... [mailto:robmurr@...]
Sent: Sunday, September 12, 1999 8:53 PM
To: 80f5@onelist.com
Subject: [80f5] test message

From: robmurr@...

is this working? had lots of trouble registering.

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is this working? had lots of trouble registering.

Sorry about this, but the screws used by the Orion #07056 rings are
8x1.25mm (not x1.5).  20mm long ones would probably be better than the
16mm ones I used.  The hole spacing is 2 3/8".

The washers supplied with the ring fit nicely into a 7/16" deep 5/8"
diameter recess bored with an inexpensive 5/8" spade bit.  The hole was
then drilled through with a 5/16" brad point bit (cleaner hole), though
a regular twist bit would do fine.

The 1/4"x20 insert hole I leave to you, depending on the type of insert
you use.  I used an allen drive threaded insert, only run in as deep as
the threads.  I then backed it out, applied glue to the wood threads,
and ran it back in again.  Finally, the unthreaded end sticking out was
filed off flush so the tripod thread would have a fully threaded insert
to connect to.

As I said, the whole process took about 20 minutes, including sanding
the results to look nice.

If anyone gets the 7056 ring in and doesn't have tools to do this, let
me know and I'll whomp up a few more of 'em as needed, cheap.  Same goes
for the cap screws and inserts, especially if you can't find them
locally.  For our metric minded friends, I'm sorry but I don't have the
standard metric drill sizes handy or I'd dimension accordingly.  But
it's trivial to measure and drill away; none of the dimensions are
critical.

Jim Horn   fog rolled in again - I guess the 'scope is still new!

In a message dated 9/12/99 1:35:30 PM Central Daylight Time,
ff77@... writes:

<< ) Jupiter – several belts, hints of detail in some.  Thomas Back using a
colour filter once told me he’d managed to spot the GRS with one of these
80mm f/5 scopes…
  7) Pluto – okay, only joking here; still if Brian Skiff can reach down to
mag 14 with a  >>


Hi Dave:

My observatons mirror yours. I'm surprised we haven't heard more about these
scopes being useful for at lest casual planetary/double star work up until
now. Perhaps the optics have gotten better over the last several years, or
perhaps a lot of 80 owners have been using bad eyepieces diagonals. Or maybe
people just didn't really try these little scopes on 'critical' subjects.
Night before last (10 September), I was able to pull out the GRS with my
Celestron 80. I spotted it first as the 'hollow' but  an 80A filter pulled it
out (green also helped too). Once I realized it was there, it was visible
unfiltered as well. Let me add that I hadn't looked at an ephemeris, so I
wasn't aware the GRS would be visible at this time--it was that unmistakable.
Very VERY pale this year, though. BTW, I've yet to see one of the Konus
scopes in person, but the pictures in Astronomy Now make the color look like
a slightly brighter shade of old Celestron Orange.

Peace,
Rod

In a message dated 9/12/99 11:05:19 AM Central Daylight Time,
jmorris@... writes:

<<
  Thanks for the report, Rod.  Your report and those of others convinced me
  that I could not live without the Eagle Optics/Celestron  80 EQ WA.  One
  cannot have too many telescopes.  I ordered it yesterday, so it will be a
  few days before it arrives.  >>


Hi Joe:

I'm very pleased with mine. I guess part of getting older is that I'm a bit
suspicious of _any_ new scope and don't expect much. Suffice to say that this
one far surpassed my expectations. I did not expect it to be _even usable_ on
the planets. The mount can stand a little tweaking here and there. But, OTOH,
I've never seen any new scope, no matter how expensive that didn't require a
"commissioning period."

Peace,
Rod

Hi, All!

Welcome aboard!  Just a quick note about mounting our telescopes.

Orion Telescopes is clearing out their #07056 mounting rings (US$15.95
plus shipping and handling and tax).  Unlike the Eagle/Celestron double
rings, it is a roughly 4" long single ring with padding at each end.  So
it braces thet tube the same as the double rings do.

Unfortunately, it has two 8x1.5 mm bolts spaced differently than the
Celestron rings are.  So it won't go on the 1/4"x20 photo tripod block
that comes with the Celestron 'scope.

The good news - I picked up some 16mm long 8x1.5 socket head cap screws
at the local hardware store and a threaded 1/4"x20 insert for under
$1.50 at the local hardware store.  I also had a piece of oak about 1.5"
x 3.5" x 3/4".  About 20 minutes with a 5/8" spade bit and 5/16" and
3/8" drill bits easily duplicated the factory block but with the
spacing for the new ring.

Results?  For about $25 total, I've got an extra mounting ring set on my
photo tripod that lets me pop the 80WA between the supplied equatorial
and a fluid damped altazimuth photo tripod.  During the day it is on the
photo tripod as our living room spotting scope.  Nights - well, we all
know about that.

More details available if interested.  I don't have a digital camera or
I'd post a picture of the results.

Jim Horn

Hi everybody,

Nice to see this little group up and running ...

As some of you may know I have posted to s.a.a. on the merits of, and how to
improve the performance of these popular 80mm f/5 instruments.  In my case I
have a Konus Vista-80.  The OTA is a bright orange-yellow colour.  Wasn't sold
on this colour at first, but have since got used to it.  In any case it was
significantly cheaper than the Orion Short Tube at the time – I’m in the UK by
the way.  I’ve had the OG in and out of its cell and the elements apart, and the
scope disassembled more times than most.  But its been worth it.  Now at 240X
using an artificial star  - I get a nice clean Airy disc and complete first and
second Airy rings.

I thought it might be fun to list a few observations with this scope and see
what others have managed.  So I thought I'd set the ball rolling.  As there are
many variants of this scope around, I guess I'd better state what set up I am
using – see below.  Anyway, first of all, here's a few observations ...

1) The double-double Epsilon Lyr - all components fairly easily split at 80X
(Airy rings visible too!).  Tried this at 54X, definite elongation but no clear
separation.  (NB. Using an artifical ‘star’ at 54X, I detect the separation
between the Airy disc and first ring.)
2) Rigel B  - both at full aperture and suprisingly stopped down with supplied
(42mm clear aperture) plastic end cap in situ.  This equals earlier detection
feats for small aperture instruments for this double cited in Burnham's
Handbook.
3) Epsilon Boo - separated at 162X; also detected the comes at 42mm aperture!
4) Saturn - Cassini division; also detected noticeable difference in brightness
of the ansae and clarity of the division in each.  Banding on the planet’s disc,
and darkening of the polar region; nice view of the ring system against the
planet, ring system edged with a thin black line.
5) Saturn again – at 54X, moons: Titan, Dione, Tethys and Rhea spotted...
6) Jupiter – several belts, hints of detail in some.  Thomas Back using a colour
filter once told me he’d managed to spot the GRS with one of these 80mm f/5
scopes…
7) Pluto – okay, only joking here; still if Brian Skiff can reach down to mag 14
with a 70mm TV Pronto, why not?!

Equipment:
Konus Vista-80
Meade 90-degree prism diagonal
32mm, 21mm, 7.4m and 1.8X and 3X TV Plossl eyepieces/barlows; 5mm Celestron
Ultima eyepiece
Manfrotto (same as Bogen) photographic tripod with fluid pan head.

Regards,
Dave Randell

Thanks for the report, Rod.  Your report and those of others convinced me
that I could not live without the Eagle Optics/Celestron  80 EQ WA.  One
cannot have too many telescopes.  I ordered it yesterday, so it will be a
few days before it arrives.  I hope I am as pleased with it as you are with
yours.  I plan to use it as a stand-alone scope and as a finder for my 8"
LX-50.  I had planned to eventually buy a Lumicon Superfinder for this
purpose, but the price of the Eagle was too good to pass up.  I may have to
get a dovetail mount for quick mounting and dismounting.  I'm not sure the
mount and rings that come with it will suffice for this purpose.  When the
ST80 arrives I will probably have some questions for those on this list more
experienced than I.  This is going to be a very timely list for me.

Regards,

Joe

Hi Gang:

Just so I can say I've posted something to the list, this is a copy of a
report on my 80 I made yesterday...

Hi Gang:

My step daughter is in her high school's marching band, so, as usual, Dorothy
and I spent our Friday evening at the Big Game. Strangely for down here, a
COLD
FRONT had passed through, moderating the temps and cleansing the sky. By the
time we got home it was around 11pm, and Jupiter was well up, with Saturn
tagging not far behind. Naturally, I grabbed my new little friend, the 80mm
Celestron WA "Short Tube," and headed for the back yard. What a joy to be able
to 'grab' a scope on the spur of the moment and trot it to the backyard!

In short order, I had the little GEM set up and the scope pointed at Jupiter.
Based on my experiences the night before, I used a good Celestron star
diagonal, the 1.25" which came with my 1995 Ultima C8. Didn't know quite what
to expect...would the entire field recreate that oldie-but-goodie, Purple
Haze!? Well, there was some color, but it was, surprisingly enough, quite
unobtrusive. And at 120x (6mm Orthoscopic, 2x barlow), MUCH detail was on
display. Including, by 1am or so--could it be?--the Great Red Spot! The GRS,
being as pale as it is, was noticed more as the "hollow" until it had rotated
well onto the planet. But it was then easily recognizable, especially with
filters, which helped reduce the glare (and eliminated The Color Purple).
Earlier on, I'd watched a shadow transit of IO. Nice! Little, hard, black BB
corssing Jove's face. I also noted that the Moons showed as tiny but
recognizable disks.

On to Saturn. Sharp. Cassini's easy, with some banding on the planet obvious.
Considerable other detail--brightness variations in the rings, etc--was
visible
when the seeing really steadied down (not that it was bad at any time!). As an
experiment, I replaced the 'good' diagonal I was using with the stock unit.
YUCK! It  _is_ a piece of junk...for 'high power' planetary observing, anyway.
It does work OK at low power.

Before I knew it, it was 2am, and I was feeling a bit weary. As a last treat,
I
turned Little Bird toward M45. How wonderful to find all the Pleiads framed in
one field! Edge sharpness was more than adequate, especially considering the
f5
speed of this telescope. I compared the included SMA 25mm Kellner to a good
Celestron black-top Plossl, and concluded that it's (the SMA) not a bad
eyepiece at all. Better, I though, than the MAs Meade used to include with
many
of their scopes (I've got several of these 'wonders' floating around here). I
wound up staring at the Sisters for some time.

Any other issues than the diagonal? Only thing so far has been the RA gear. It
worked fine most of the time last night, but would occasionally tend to bind.
The worm is adjustable, so I fiddled with it a bit this morning, and managed
to
eliminate the binding without much trouble. I could probably adjust it a bit
further to eliminate a bit of slop, but it is now working well. The mount
basically arrived with no/very little lubrication anywhere, but Pat Rochford
and I will disassemble and correct that as necessary some time this coming
week. Again, this small GEM is well suited to this scope, with a sharp rap
dying out in about 2 seconds at 120x.

I was, in summary, bowled-over by the scope's planetary performance.
Unfortunately, a user who didn't know to change-out the el cheapo diagonal
would never realize this. I suppose it's possible that I just got a bad one,
but from what I'm hearing from the purchasers of a number of Celestron's
scopes, poorer star diagonals now, unfortunately, seem to be the rule rather
than the exception.

What's next? Tonight, I stack barlows! :-)


Peace,
Rod Mollise
Mobile Astronomical Society
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