Big Dobs have two critical problems.

(1) Cooldown.  The mirrors are massive and thermal issues are huge,
and fans help a great deal but still leave a lot to be desired.
(2) Collimation.  Obsession's more recent designs recognize that the
previous designs were inadequate for allowing a mirror to hold
collimation.  The biggest dobs had bolts that were too thin to hold
the sling, and flexed.  Also, the sling itself stretched when it got
wet.  Obsession has redesigned the mirror sling arrangement but it
remains a problematic element of the design.

For these and perhaps other reasons well-tuned scts can offer fine
views that will outperform big dobs "at least as often as not."  The
central obstruction is a bogus issue. (see Damian Peach's recent
images of Saturn with a 9.25). The main performance issue is
cooldown and collimation on almost any scope.

regards
Greg N

--- In sct-user@yahoogroups.com, "gstrumol" <gstrumol@c...> wrote:
  The excellent rep these Obsession scopes have led
> us
> > to blame the poor performance on collimation. I am unsure. Was
the
> > aperture just too large? We should give it another go next star
> > party, hopefully with more diligent collimation. As for multiple
> > reflections/ghosts in Naglers, personally I have never noticed
it.

See <http://skyandtelescope.com/resources/organizations/> for a list of
clubs in your area.
-John

--- "Stanley Fisher, Ph.D." <sfisher@...> wrote:
>
> Hi -
> I'm trying to learn to use my ETX90EC and would love to find more
> experienced users in the city I could learn from.
> Stan




__________________________________
Do you Yahoo!?
Meet the all-new My Yahoo! - Try it today!
http://my.yahoo.com

Hello Fellow Astronomers...and Rock Hounds of all ages,

This posting has been cleared by the owner/moderator so don't delete
it yet.

I am proud to announce that we astronomy nerds now have a new Yahoo
group dedicated to meteorite hunting. You are hereby invited to join
http://groups.yahoo.com/group/meteorite_hunters to share your
knowledge on how to chase and locate iron, stoney and stoney-iron
meteorites.

They're scattered just about everywhere around the world. We're
bombarded by these extraterrestial visitors 24-hours a day/night.
All we need to do is find them. If you have some expertise on how to
chase that bolide you saw last night and techniques for finding them
and are willing to share your information with us beginners, this is
the group to join.

Bill "Flaming Rock" Logan
Owner/Moderator

> we normally have a TV 140mm APO ...

Televue doesn't make a 140mm APO as far as I know ...

Gary

--- In sct-user@yahoogroups.com, "Samir Kharusi" <samirkharusi@h...>
wrote:
>
> I am making a connection between the desperation of eking out the
> very last little bit of performance from a small aperture (most
APOs
> under $30,000?) and the much-diminished desperation when using
ample
> aperture (larger SCT). At our star parties we normally have a TV
> 140mm APO next to a less than perfectly collimated C11, and no
> shortage of eyepieces to try out. Anyone who looks at a planet in
> the two scopes immediately abandons the APO. Aperture inches do
> matter (up to some limit, 16"?) for planetary viewing. I do
believe
> that the TV APO meets much higher optical standards than the C11,
> but despite all that, the light bucket wins out. Last star party
we
> also tried out a 20" Obsession and frankly, it was quite unusable
> for planetary. The excellent rep these Obsession scopes have led
us
> to blame the poor performance on collimation. I am unsure. Was the
> aperture just too large? We should give it another go next star
> party, hopefully with more diligent collimation. As for multiple
> reflections/ghosts in Naglers, personally I have never noticed it.
> Perhaps mine had newer coatings than yours? Of course, now that
you
> have mentioned it, I'll probably notice them :-( and I am going to
> blame it all on you, personally ;-)
>
> --- In sct-user@yahoogroups.com, John Mahony <jmmahony@y...> wrote:
> >
> > --- Samir Kharusi <samirkharusi@h...> wrote:
> > >
> > > Couple of opinions:
> > > The R/C just adds unnecessary glass elements which will lower
> > > contrast. The UO Orthos are made deliberately to have very few
> > > elements in order to maintain contrast, like all planetary
> > > eyepieces. Rather contradictory? These so-called planetary
> eyepieces
> > > are really for the APOs with their tiny apertures. You have
8".
> > > Relax and enjoy the aperture.
> >
> > I don't understand.  Are you making a connection between
contrast
> and
> > aperture?  Planets are bright even in a small scope.  Using
larger
> > aperture makes the planets brighter, but it also makes the
> scattered
> > light brighter, so the contrast is the same.
> >
> > TV EPs do have a very fine polish on the lens elements, so
> scattering
> > isn't bad compared even to orthos, but all those extra elements
> cause
> > a bad ghosting problem when you have a small bright object in the
> > field.  In fact, I've found that I don't need to use a reticle
EP
> for
> > precise centering when doing the initial alignment:  I just move
> the
> > scope until all the ghost images line up with the alignment
star!
> >
> > -John
> >
> >
> >
> >
> >
> > __________________________________
> > Do you Yahoo!?
> > Jazz up your holiday email with celebrity designs. Learn more.
> > http://celebrity.mail.yahoo.com

Kinda 'OT', but since it affects us all....
Please take a moment from your busy schedules and consider signing the
petition against light pollution at:
  http://www.petitiononline.com/darksky1/petition.html

Mucho Thanks!
~S*H

Learn how to TRIM your messages, PLEASE!!!!

Hi Rod,
I was about to order the JMI focuser, when I read the customer reviews on the
Anacortes web site. Those reviews don't seem to give high ratings to this
focuser, especially the first review by Timothy Libert
(http://www.buytelescopes.com/product.asp?m=&pid=1236&display=reviews). Do you
have any idea if these reviews are old and if JMI changed anything about it?

Thanks,
Eddy


   ----- Original Message -----
   From: RMOLLISE@...
   To: sct-user@yahoogroups.com
   Sent: Thursday, 30 December, 2004 13:23
   Subject: Re: [sct-user] Crayford focusers


   In a message dated 12/30/2004 2:14:14 AM Eastern Standard Time, "Eddy"
<EddyDel5@...> writes:


   Hi:


   >1. So, do you need that "dual speed" on a SCT, since you can roughly
   >focus with the original focuser and than, I guess, fine tune with
   >the Crayford? The Feathertouch and Moonlite cost both about the
   >double of the JMI or WO ones.

   If you're a planetary imager working at high focal ratios, you should consider
this. Otherwise...I deem it "nice but not needed."



   >2. Apart from the advantage that you can add a motorized focusing
   >system to the JMI one, which one of the "cheaper" ones, do you think
   >is the "best"?

   I think the WO or the JMI make the most sense.


   >3. Also won't there be a problem with focusing after all since you
   >are adding another piece of equipment between the visual back and
   >the star diagonal?


   Only if you add focal reducers ahead of the focuser.

   >
   >
   >
   >


   --
   Peace,
   Rod Mollise
   Author of:_Choosing and Using a Schmidt Cassegrain Telescope_
   <http://members.aol.com/RMOLLISE/index.html>



   Visit the sct-user home page at:



   http://members.aol.com/RMOLLISE/index4.html


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[Non-text portions of this message have been removed]

R Hamlett wrote:
>  > My experience with the Meade 6.3 FR and the NS11 has been quite
> different.
>  >
>  > My FR may well be a dud (its the only one I've tried), but I find that
>  > images obtained using it are softer and lack snap.
SNIP

>  > Best regards,
>  >
>  > Richard Jordan
> I wonder what your actual optical setup is?. Historically, if you put the
> reducer as close as possible to the rear port of the scope, and then add a
> 1.25" diagonal, the scope is operating very close to it's design distance
> (the backfocus at the reducer, is about 5", against a design distance of
> about 4"). This gives very slightly more SA in the scope, than without the
> reducer, but the much flatter field, really does show in the eyepiece.
> However if (for instance), the reducer is operated with a 2" diagonal,
> without taking measures to keep the distances short, the reducer starts to
> give much more reduction, and the backfocus needed 'shoots' up. If you then
> attach this behind a crayford focusser, the scope can instead be operating
> needing well more than a foot of backfocus, and the reducer itself is also
> operating well away from it's design criteria.
> The reducer needs to be used with care, but the softness you are seeing,
> suggests that perhaps the setup you have is 'pushing' some aspect of the
> design.
>
> Best Wishes

Roger:

Right you are, that's the way I understand it too.  I always use the FR
screwed directly onto the rear port of the SCT. I don't use any focuser
other than the one in the scope.  I use both the 2" and 1 1/4" set ups.
   With the 2", I use a TV connector into a refractor style TV Everbrite
diagonal with both 2" and 1 1/4 EPs.  I also have a 2" Meade SCT style
diagonal that screws directly onto the FR.  With the 1 1/4 prism
diagonal that came with the scope, I use a visual back that screws
directly onto the RC.

Here's what I find using double stars on what is a rare good night for me:

best using RC, RC + 1 1/4 visual back + 1/1/4 prism + EP
next best, RC + Meade 2" SCT diagonal + EP, to use 1 1/4 EPs I use a low
profile adapter that adds a bit of distance
next best, RC + TV 2" adapter + Everbrite diagonal

These differences are also apparent to me observing the Double Cluster
in Perseus.  The delicate dim stars as great little test objects.

I also note that I get the best high power images without the RC using
the 1 1/4 visual back + 1 1/4 prism diagonal.  These days, I only have
one 2" EP, a 22mm Nagler T4. Using the T4 is the only time I use the 2"
equipment on the NS11.

As I mentioned, I may have a bad RC, but I haven't heard anyone say they
ever got a bad one.  So the best I can do is give my experience, qualify
it and say YMMV.

Best regards and every success in 2005,

Richard JOrdan


--
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Checked by AVG Anti-Virus.
Version: 7.0.298 / Virus Database: 265.6.7 - Release Date: 12/30/2004

Samir,

Your experience with the 20" was probably due to "seeing". Large
aperture instruments are much more susceptible to seeing than small
aperture scopes...

cheers,
Chris

--- In sct-user@yahoogroups.com, "Samir Kharusi" <samirkharusi@h...>
wrote:
>
> I am making a connection between the desperation of eking out the
> very last little bit of performance from a small aperture (most APOs
> under $30,000?) and the much-diminished desperation when using ample
> aperture (larger SCT). At our star parties we normally have a TV
> 140mm APO next to a less than perfectly collimated C11, and no
> shortage of eyepieces to try out. Anyone who looks at a planet in
> the two scopes immediately abandons the APO. Aperture inches do
> matter (up to some limit, 16"?) for planetary viewing. I do believe
> that the TV APO meets much higher optical standards than the C11,
> but despite all that, the light bucket wins out. Last star party we
> also tried out a 20" Obsession and frankly, it was quite unusable
> for planetary. The excellent rep these Obsession scopes have led us
> to blame the poor performance on collimation. I am unsure. Was the
> aperture just too large? We should give it another go next star
> party, hopefully with more diligent collimation. As for multiple
> reflections/ghosts in Naglers, personally I have never noticed it.
> Perhaps mine had newer coatings than yours? Of course, now that you
> have mentioned it, I'll probably notice them :-( and I am going to
> blame it all on you, personally ;-)

--- In sct-user@yahoogroups.com, "Samir Kharusi" <samirkharusi@h...>
wrote:
>
> Couple of opinions:
> The R/C just adds unnecessary glass elements which will lower
> contrast. The UO Orthos are made deliberately to have very few
> elements in order to maintain contrast, like all planetary
> eyepieces. Rather contradictory? These so-called planetary eyepieces
> are really for the APOs with their tiny apertures. You have 8".
> Relax and enjoy the aperture.

It's not an APO or aperture issue - it's a focal length issue...

cheers,
Chris

> My experience with the Meade 6.3 FR and the NS11 has been quite
different.
>
> My FR may well be a dud (its the only one I've tried), but I find that
> images obtained using it are softer and lack snap.  This tendency gets
> worse as the power increases.  I've always attributed this to spherical
> aberration due to a change in the position of the primary mirror from
> optimal in order to focus using the FR.  Yes, I've collimated with the
> RC in place.
>
> I doubt that the number of glass surfaces has much to do with the
> problem because well executed multi-element designs have superb light
> transmission, as is the case of my 22mm Nagler.
>
> I know this goes against the grain, but for visual use, I'd recommend a
> try before you buy if at all possible.
>
> Best regards,
>
> Richard Jordan
I wonder what your actual optical setup is?. Historically, if you put the
reducer as close as possible to the rear port of the scope, and then add a
1.25" diagonal, the scope is operating very close to it's design distance
(the backfocus at the reducer, is about 5", against a design distance of
about 4"). This gives very slightly more SA in the scope, than without the
reducer, but the much flatter field, really does show in the eyepiece.
However if (for instance), the reducer is operated with a 2" diagonal,
without taking measures to keep the distances short, the reducer starts to
give much more reduction, and the backfocus needed 'shoots' up. If you then
attach this behind a crayford focusser, the scope can instead be operating
needing well more than a foot of backfocus, and the reducer itself is also
operating well away from it's design criteria.
The reducer needs to be used with care, but the softness you are seeing,
suggests that perhaps the setup you have is 'pushing' some aspect of the
design.

Best Wishes

I am making a connection between the desperation of eking out the
very last little bit of performance from a small aperture (most APOs
under $30,000?) and the much-diminished desperation when using ample
aperture (larger SCT). At our star parties we normally have a TV
140mm APO next to a less than perfectly collimated C11, and no
shortage of eyepieces to try out. Anyone who looks at a planet in
the two scopes immediately abandons the APO. Aperture inches do
matter (up to some limit, 16"?) for planetary viewing. I do believe
that the TV APO meets much higher optical standards than the C11,
but despite all that, the light bucket wins out. Last star party we
also tried out a 20" Obsession and frankly, it was quite unusable
for planetary. The excellent rep these Obsession scopes have led us
to blame the poor performance on collimation. I am unsure. Was the
aperture just too large? We should give it another go next star
party, hopefully with more diligent collimation. As for multiple
reflections/ghosts in Naglers, personally I have never noticed it.
Perhaps mine had newer coatings than yours? Of course, now that you
have mentioned it, I'll probably notice them :-( and I am going to
blame it all on you, personally ;-)

--- In sct-user@yahoogroups.com, John Mahony <jmmahony@y...> wrote:
>
> --- Samir Kharusi <samirkharusi@h...> wrote:
> >
> > Couple of opinions:
> > The R/C just adds unnecessary glass elements which will lower
> > contrast. The UO Orthos are made deliberately to have very few
> > elements in order to maintain contrast, like all planetary
> > eyepieces. Rather contradictory? These so-called planetary
eyepieces
> > are really for the APOs with their tiny apertures. You have 8".
> > Relax and enjoy the aperture.
>
> I don't understand.  Are you making a connection between contrast
and
> aperture?  Planets are bright even in a small scope.  Using larger
> aperture makes the planets brighter, but it also makes the
scattered
> light brighter, so the contrast is the same.
>
> TV EPs do have a very fine polish on the lens elements, so
scattering
> isn't bad compared even to orthos, but all those extra elements
cause
> a bad ghosting problem when you have a small bright object in the
> field.  In fact, I've found that I don't need to use a reticle EP
for
> precise centering when doing the initial alignment:  I just move
the
> scope until all the ghost images line up with the alignment star!
>
> -John
>
>
>
>
>
> __________________________________
> Do you Yahoo!?
> Jazz up your holiday email with celebrity designs. Learn more.
> http://celebrity.mail.yahoo.com

Nice site as usual. Download time worth it. Just finished viewing with
my 15x50 IS Canon binoculars from the heart of New York City.

Dennis Persyk wrote:
>
> I imaged Q2 Machholz and have a movie showing its motion across the
> sky during a 96 minute period.  The comet was clearly visible under
> the full moon with the C-11 scope at 93x, but quite difficult to
> find in the 7x50 binoculars. Transparency was 2/10 Pickering with
> high thin clouds.
>
> Finder chart, isophotes, movie, image and supporting data at
> http://home.att.net/~dpersyk/new.htm
>
> This web page is a bit larger than my usual ones, so I'd appreciate
> feedback from my modem viewers as to download time – is it
> acceptable?
>
> Thank you for visiting my site.
>
> Clear skies,
>
> Dennis Persyk
> Igloo Observatory Home Page http://dpersyk.home.att.net
> Hampshire, IL
>
> Visit the sct-user home page at:
>
> http://members.aol.com/RMOLLISE/index4.html
> Yahoo! Groups Links
>
>
>
>

Hi -
I'm trying to learn to use my ETX90EC and would love to find more
experienced users in the city I could learn from.
Stan

--- Samir Kharusi <samirkharusi@...> wrote:
>
> Couple of opinions:
> The R/C just adds unnecessary glass elements which will lower
> contrast. The UO Orthos are made deliberately to have very few
> elements in order to maintain contrast, like all planetary
> eyepieces. Rather contradictory? These so-called planetary eyepieces
> are really for the APOs with their tiny apertures. You have 8".
> Relax and enjoy the aperture.

I don't understand.  Are you making a connection between contrast and
aperture?  Planets are bright even in a small scope.  Using larger
aperture makes the planets brighter, but it also makes the scattered
light brighter, so the contrast is the same.

TV EPs do have a very fine polish on the lens elements, so scattering
isn't bad compared even to orthos, but all those extra elements cause
a bad ghosting problem when you have a small bright object in the
field.  In fact, I've found that I don't need to use a reticle EP for
precise centering when doing the initial alignment:  I just move the
scope until all the ghost images line up with the alignment star!

-John





__________________________________
Do you Yahoo!?
Jazz up your holiday email with celebrity designs. Learn more.
http://celebrity.mail.yahoo.com

--- In sct-user@yahoogroups.com, "Dennis Persyk" <dpersyk@a...> wrote:
>
> I imaged Q2 Machholz and have a movie showing its motion across the
> sky during a 96 minute period.  The comet was clearly visible under
> the full moon with the C-11 scope at 93x, but quite difficult to
> find in the 7x50 binoculars. Transparency was 2/10 Pickering with
> high thin clouds.
>
> Finder chart, isophotes, movie, image and supporting data at
> http://home.att.net/~dpersyk/new.htm
>
> This web page is a bit larger than my usual ones, so I'd appreciate
> feedback from my modem viewers as to download time – is it
> acceptable?
^^^^^^^^^^^^^^^^^^^^^

Hi Dennis;
Excellent work with the iceball, as usual for you.  The page loads as
well as should be expected on a dialup, no problem at all.  The only
thing I had to 'wait' at all for was the movie, and even that was
negligible.

Good timing with the presentation also -- on the night of 30th/31st AM
I spent a good deal of time making an in depth study of Machholz
trying different filtering in light-thru-deep blues, yellows, and red
& orange, even an UltraBlock & O-III 'for giggles', and across a range
of magnifications (40mm, 32mm, 26mm Plossls; 15mm TV Widefield; 10.5mm
Pentax XL; and 7mm Nagler) to study what effects they had in
distinguishing details & highlights of the dust & gas tails as well as
the coma & nucleus.  The best that all that could bring out was, to
use the term I recorded on my voice transcript, a 'spikelet' of a tail
towards the 2 o'clock position in the EP, at best only as wide as the
head immediately at the head, and narrowing quickly for the few
arcseconds it extended.  This darn near exactly as it appears in your
'negative' image....hence my remark about good timing, as it helps to
confirm my findings, in both size and direction.  So too, thanks for
your post! ~8)

Even tho the seeing was unsteady, had good fun doing this work; a rare
night of clear sky before Luna showed her face, plus >very<
unseasonable warmth for this time of year (it had hit 70F during the
day!) made it a comfortable endeavor as well, only requiring a hooded
sweatshirt to ward off the slight chill.  By the time the moon climbed
from behind the trees, the sky soon afterward quickly deteriorated as
clouds began closing it off in ever-thickening 'banding' wisps as
precursors of the front started coming in.  With it, the dewing
started as well (I had used only a dew shield until around 1AM-ish, no
heaters) so, with the sky closing down I didn't get to move to DSOs as
was my plan (doing research on galaxys etc visible in moonlight), so
shut down & moved back inside.  Wouldn't wanta keep the New Year's Elf
from appearing! *LOL*

To clarity!
~Star*Hopper

-----Original Message-----
From: RMOLLISE@... [mailto:RMOLLISE@...]
Sent: Saturday, January 01, 2005 10:21 AM
To: sct-user@yahoogroups.com
Subject: Re: [sct-user] Meade's announcement



>> But, I understand, the buyers
thought they didn't "look enough like telescopes," and insisted Meade
provide
the typical 60x700 jobs for the following season.<<

Glad Austin Nichols never had a similar problem with the cork!  :-)

Happy New Year everyone!

Rob






--
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Checked by AVG Anti-Virus.
Version: 7.0.296 / Virus Database: 265.6.5 - Release Date: 12/26/2004

--
No virus found in this outgoing message.
Checked by AVG Anti-Virus.
Version: 7.0.296 / Virus Database: 265.6.5 - Release Date: 12/26/2004

Hi Dennis,

Always enjoy your images.  The page took less than 30 sec. to load @ 26.4k.
Definitely acceptable.

Clear skies,

Rob

-----Original Message-----
From: Dennis Persyk [mailto:dpersyk@...]
Sent: Saturday, January 01, 2005 12:29 PM
To: sct-user@yahoogroups.com
Subject: [sct-user] Q2 Machholz Movie




I imaged Q2 Machholz and have a movie showing its motion across the
sky during a 96 minute period.  The comet was clearly visible under
the full moon with the C-11 scope at 93x, but quite difficult to
find in the 7x50 binoculars. Transparency was 2/10 Pickering with
high thin clouds.

Finder chart, isophotes, movie, image and supporting data at
http://home.att.net/~dpersyk/new.htm

This web page is a bit larger than my usual ones, so I'd appreciate
feedback from my modem viewers as to download time – is it
acceptable?

Thank you for visiting my site.

Clear skies,

Dennis Persyk
Igloo Observatory Home Page http://dpersyk.home.att.net
Hampshire, IL






Visit the sct-user home page at:



http://members.aol.com/RMOLLISE/index4.html
Yahoo! Groups Links







--
No virus found in this incoming message.
Checked by AVG Anti-Virus.
Version: 7.0.296 / Virus Database: 265.6.5 - Release Date: 12/26/2004

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No virus found in this outgoing message.
Checked by AVG Anti-Virus.
Version: 7.0.296 / Virus Database: 265.6.5 - Release Date: 12/26/2004

Hi Dennis
Nice movie.  I can definitely see the effects of high clouds.

On broadband, it loads so fast as to not be noticable.

---------
Phil Chambers [ptchamb@...] (S.F. Bay Area - Calif. USA)

On Sat, 1 Jan 2005, Dennis Persyk wrote:

>
>
> I imaged Q2 Machholz and have a movie showing its motion across the
> sky during a 96 minute period.  The comet was clearly visible under
> the full moon with the C-11 scope at 93x, but quite difficult to
> find in the 7x50 binoculars. Transparency was 2/10 Pickering with
> high thin clouds.
>
> Finder chart, isophotes, movie, image and supporting data at
> http://home.att.net/~dpersyk/new.htm
>
> This web page is a bit larger than my usual ones, so I'd appreciate
> feedback from my modem viewers as to download time – is it
> acceptable?
>
> Thank you for visiting my site.
>
> Clear skies,
>
> Dennis Persyk
> Igloo Observatory Home Page http://dpersyk.home.att.net
> Hampshire, IL
>
>
>
>
>
>
> Visit the sct-user home page at:
>
>
>
> http://members.aol.com/RMOLLISE/index4.html
> Yahoo! Groups Links
>
>
>
>
>
>
>
>
>

I imaged Q2 Machholz and have a movie showing its motion across the
sky during a 96 minute period.  The comet was clearly visible under
the full moon with the C-11 scope at 93x, but quite difficult to
find in the 7x50 binoculars. Transparency was 2/10 Pickering with
high thin clouds.

Finder chart, isophotes, movie, image and supporting data at
http://home.att.net/~dpersyk/new.htm

This web page is a bit larger than my usual ones, so I'd appreciate
feedback from my modem viewers as to download time – is it
acceptable?

Thank you for visiting my site.

Clear skies,

Dennis Persyk
Igloo Observatory Home Page http://dpersyk.home.att.net
Hampshire, IL

Ken Hutchinson wrote:
>
> --- In sct-user@yahoogroups.com, Chris Rowland <chris_group_mail@d...> wrote:
>
>>I can't stand it any more :-)
>>
>>What are you talking about?
>>
>>Chris
>
>
> Orion is offering a 3.6"/91mm Herschelian/Newtonian telescope.

Thanks,

Chris

In a message dated 12/31/04 4:29:02 PM Central Standard Time,
wb9sat@... writes:
Gosh! Wonder what the new announcement is going to be. Hope it's new product
line is better than the cheap discount department store holiday trash scopes
that they've flooded the market with.

Hi Bill:

It's no secret that Meade AND Celestron have both sold telescopes of this
type over the last 20 years. Lots of them. I doubt that's going to change.
Beleive it or not, the profit is not in the equipment you and I crave. It's in
the
inexpensive telescopes and binocs they ship to Wal-Mart. And, as far as that
goes, what they ship is dependent on what the store chain's buyer wants.
WallyWorld, those in this area, anyway, were selling ETX 60s for one season,
actually. These were nice and workable little scopes. But, I understand, the
buyers
thought they didn't "look enough like telescopes," and insisted Meade provide
the typical 60x700 jobs for the following season.


Peace,
Rod Mollise
Author of:_Choosing and Using a Schmidt Cassegrain Telescope_
http://members.aol.com/RMOLLISE/index.html


[Non-text portions of this message have been removed]

To all CAT lovers,
i wish you an happy new year. Plenty of health to continue using our time
machines, plenty of clear skies ( yeah i'm dreaming right now...i know ! ) to
continue enjoying our same passion of the night sky.

No matter the brand we own, the size, the age, what we're doing with our CAT (
God bless diversity ), where we live on Earth, we have to remember the main
purpose of our presence on Uncle's Rod Group : Our passion for CAT.


Happy to be with you all on this group, have an excellent year 2005.


Frederic Caron
www.quebec-astro.com


[Non-text portions of this message have been removed]

Hi, another opinion.   I have an N11 and definitely did notice a slight increase
in contrast with my AP 12mm SPL over my 12mm Radian.  I spent about 3 nights
doing A/B comparisons before I sold my 12mm Radian.   I'll never sell my 14mm
Radian though!   I love it for smaller DSOs and planets on nights the seeing
won't support 240x.  Also the eye relief is great.

Chuck
   ----- Original Message -----
   From: Samir Kharusi
   To: sct-user@yahoogroups.com
   Sent: Saturday, January 01, 2005 4:40 AM
   Subject: [sct-user] Re: 6.3 r/c and planetary viewing



   Couple of opinions:
   The R/C just adds unnecessary glass elements which will lower
   contrast. The UO Orthos are made deliberately to have very few
   elements in order to maintain contrast, like all planetary
   eyepieces. Rather contradictory? These so-called planetary eyepieces
   are really for the APOs with their tiny apertures. You have 8".
   Relax and enjoy the aperture.

   Personally I simply hate the narrow FoV of so-called planetary
   eyepieces. According to Al Nagler, all Televue eyepieces are
   diffraction-limited centrally, so unless you really, really are
   chasing that last bit of contrast (with an sct?!) why not just get a
   very pleasant, comfortable ultra-wide eyepiece like a Nagler (or one
   of the new Meades) that yields 300x on your naked (no R/C) OTA.
   Chasing the planets is a non-issue because of the wide FoV and you
   get to see all the moons in one go :-) I used to use a 7mm Nagler on
   the C8. On a C14 I use a 13mm Nagler. You will likely never need
   more than 300x magnification on a C8 (provided your vision is
   normal) and if your seeing is really lousy on any given night you
   can always stick in that R/C, but then why observe planets on a
   night with lousy seeing? Actually even on a C14 I find going beyond
   300x is mostly useless because of seeing limitations. On an extra
   special night I suppose I can always stick in a Barlow to that 13mm.
   Sold the 7mm with the C8. Anyway everyone has an opinion on
   eyepieces... Just my 2 cents ;-)

   > --- MKCinibulk <mecinibulk@e...> wrote:
   > >
   > > I really like the r/c on my C-8 for general purpose viewing and
   am
   > > trying to decide on an eyepiece for planetary viewing. I've
   decide
   > > on the UO HD orthos, but can't decide on which focal length.
   This
   > > depends on whether I should take off the r/c for planetary
   viewing.
   > > If I take it off I would get the 9 mm for 226X mag. If I leave
   the
   > > r/c on, i would go with a 12 mm plus my ultima barlow, which is
   2.4X
   > > in my C-8, for 256X mag.
   > >
   > > How many of you view planets with the r/c in place? Has anyone
   > > critically compared the views with and without the r/c at
   similar
   > > mags on planets? It's just that removing the r/c is a hassle.
   > >
   > > -Mike
   > >
   > >
   > >
   > >
   > >
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   > >
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   > >
   > >
   > >
   > > http://members.aol.com/RMOLLISE/index4.html
   > > Yahoo! Groups Links
   > >
   > >
   > >
   > >
   > >
   > >
   > >
   > >
   >
   >
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[Non-text portions of this message have been removed]

I have been using a Williams Optics focuser on my 8" LX200 classic
for about 6 months now, I agree it's a useful add-on for high power
use, but I would say my biggest improvement in ease of focusing was a
Peterson Engineering EZ Focus kit. This reduces focuser backlash to
zero and makes the whole thing feel so much smoother and more
precise - it takes away all the 'stiction' you get with the standard
plastic bearings. It's pretty simple to fit and doesn't add any
weight onto the scope. Obviously you will still get a degree of image
shift, but if you can live with it, treating the focus problems
nearer to the cause (i.e. the mechanism that moves the primary) makes
a lot of sense.

Hi.  I'm a new member and relatively new to astronomy.  I did naked
eye and binocular astronomy for a year and now do some viewing w/
telescopes.  I have an off-axis Newtonian 3.6" f/11 from DGM, a100mm
achromatic refractor, and now have agreed to purchase an Intes Micro
Alter M603 6"f/10.  I'll be getting an Alt/Az mount from Universal
Astronomics.  I'm acquainted w/ Russian Optics as i have 16x50
Russian Image Stabilized binoculars.  I can hand-held split doubles
w/ these better than I can w/ 20x80 Chinese binoculars mounted on a
tripod. I also have a Tal 22mm plossl and a Tal 26mm wide view
eyepiece.  I'll have the Intes outside at work most of the time so
cool-down time shouldn't be a problem.  Do any of you have
experience w/ this telescope as to performance vis avis doubles,
clusters etc.?

--- In sct-user@yahoogroups.com, Chris Rowland <chris_group_mail@d...> wrote:
>
> I can't stand it any more :-)
>
> What are you talking about?
>
> Chris

Orion is offering a 3.6"/91mm Herschelian/Newtonian telescope.

http://www.telescope.com/shopping/product/detailmain.jsp?
itemID=77066&itemType=PRODUCT&iMainCat=4&iSubCat=8&iProductID=77066

It is an interesting idea but you can do the same thing at
almost the same cost by putting an off-axis aperture mask
on a larger reflector (or CAT!) so that the aperture is
unobstructed. One feature of an APO that this approach
cannot duplicate is the focal ratio. You are stuck with
a pretty long focal ratio when you do this.

Ken

Couple of opinions:
The R/C just adds unnecessary glass elements which will lower
contrast. The UO Orthos are made deliberately to have very few
elements in order to maintain contrast, like all planetary
eyepieces. Rather contradictory? These so-called planetary eyepieces
are really for the APOs with their tiny apertures. You have 8".
Relax and enjoy the aperture.

Personally I simply hate the narrow FoV of so-called planetary
eyepieces. According to Al Nagler, all Televue eyepieces are
diffraction-limited centrally, so unless you really, really are
chasing that last bit of contrast (with an sct?!) why not just get a
very pleasant, comfortable ultra-wide eyepiece like a Nagler (or one
of the new Meades) that yields 300x on your naked (no R/C) OTA.
Chasing the planets is a non-issue because of the wide FoV and you
get to see all the moons in one go :-) I used to use a 7mm Nagler on
the C8. On a C14 I use a 13mm Nagler. You will likely never need
more than 300x magnification on a C8 (provided your vision is
normal) and if your seeing is really lousy on any given night you
can always stick in that R/C, but then why observe planets on a
night with lousy seeing? Actually even on a C14 I find going beyond
300x is mostly useless because of seeing limitations. On an extra
special night I suppose I can always stick in a Barlow to that 13mm.
Sold the 7mm with the C8. Anyway everyone has an opinion on
eyepieces... Just my 2 cents ;-)

> --- MKCinibulk <mecinibulk@e...> wrote:
> >
> > I really like the r/c on my C-8 for general purpose viewing and
am
> > trying to decide on an eyepiece for planetary viewing. I've
decide
> > on the UO HD orthos, but can't decide on which focal length.
This
> > depends on whether I should take off the r/c for planetary
viewing.
> > If I take it off I would get the 9 mm for 226X mag. If I leave
the
> > r/c on, i would go with a 12 mm plus my ultima barlow, which is
2.4X
> > in my C-8, for 256X mag.
> >
> > How many of you view planets with the r/c in place? Has anyone
> > critically compared the views with and without the r/c at
similar
> > mags on planets? It's just that removing the r/c is a hassle.
> >
> > -Mike
> >
> >
> >
> >
> >
> > ------------------------ Yahoo! Groups Sponsor
> > --------------------~-->
> > $4.98 domain names from Yahoo!. Register anything.
> > http://us.click.yahoo.com/Q7_YsB/neXJAA/yQLSAA/1.XolB/TM
> >
> -------------------------------------------------------------------
-~->
> >
> >
> > Visit the sct-user home page at:
> >
> >
> >
> > http://members.aol.com/RMOLLISE/index4.html
> > Yahoo! Groups Links
> >
> >
> >
> >
> >
> >
> >
> >
>
>
> __________________________________________________
> Do You Yahoo!?
> Tired of spam?  Yahoo! Mail has the best spam protection around
> http://mail.yahoo.com

Hi,
I've been trying to get this on through, but had some problems with bouncing
email. So here I try again.

I checked with my usual dealer and they have only the JMI in stock. The WO is on
back order for some time. After what you guys told me, I considered going  for
one of these (WO or JMI), but since I am not the kind of person that can wait
when I want something, it's going to be the JMI. One last taught though. I've
been reading a lot of stuff about people having trouble adding some equipment on
their scope with a Crayford focuser (load factor). Is there going to be any
problem with it?

Thanks,
Eddy
   ----- Original Message -----
   From: Trevor
   To: sct-user@yahoogroups.com
   Sent: Friday, 31 December, 2004 00:17
   Subject: RE: [sct-user] Crayford focusers


   Hello Eddy
                   Please let us know what you decide as it may help other
   to up grade.





   Cheers Trev
   Visit www.wig1.co.uk <http://www.wig1.co.uk/>

   to see what the BRATS are up to

   51.23 N 00.24..E

   N. Kent

   S.E UK





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   -----Original Message-----
   From: Eddy [mailto:EddyDel5@...]
   Sent: 30 December 2004 17:58
   To: sct-user@yahoogroups.com
   Subject: Re: [sct-user] Crayford focusers


   Thanks a lot for all the info you've been sending me.
   It'll be up to me to decide.
   Happy New Year everybody,
   Eddy
     ----- Original Message -----
     From: RMOLLISE@...
     To: sct-user@yahoogroups.com
     Sent: Thursday, 30 December, 2004 13:23
     Subject: Re: [sct-user] Crayford focusers


     In a message dated 12/30/2004 2:14:14 AM Eastern Standard Time, "Eddy"
   <EddyDel5@...> writes:


     Hi:


     >1. So, do you need that "dual speed" on a SCT, since you can roughly
     >focus with the original focuser and than, I guess, fine tune with
     >the Crayford? The Feathertouch and Moonlite cost both about the
     >double of the JMI or WO ones.

     If you're a planetary imager working at high focal ratios, you should
   consider this. Otherwise...I deem it "nice but not needed."



     >2. Apart from the advantage that you can add a motorized focusing
     >system to the JMI one, which one of the "cheaper" ones, do you think
     >is the "best"?

     I think the WO or the JMI make the most sense.


     >3. Also won't there be a problem with focusing after all since you
     >are adding another piece of equipment between the visual back and
     >the star diagonal?


     Only if you add focal reducers ahead of the focuser.

     >
     >
     >
     >


     --
     Peace,
     Rod Mollise
     Author of:_Choosing and Using a Schmidt Cassegrain Telescope_
     <http://members.aol.com/RMOLLISE/index.html>



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[Non-text portions of this message have been removed]

Ken Hutchinson wrote:
>
> --- In sct-user@yahoogroups.com, RMOLLISE@a... wrote:
>
>>In a message dated 12/31/04 9:07:50 AM Central Standard Time,
>>gstrumol@c... writes:
>>Maybe they will come out with a clear aperture Newtonian that
>>eliminates the effect of CO, ... wait a minute ...
>>
>>Hi Gary:
>>
>>And has a 3 inch aperture and sells for a 1000 smackers on an EQ4 mount?
>>Seems to me somebody just tried that and it is going straight into the toilet.
;-)
>>
>
>
> Come now guys, it's not that bad. You get a 91mm "APO" for $150
> more than the 80ED and $350 less than the 100ED. The ED's have
> nicer mechanicals and their focal ratios are better for wide views.
> I think the worst part about the off axis reflector is that for $300
> more you could have the 10" on the Atlas mount and make your
> own (if you wanted to) with an aperture mask. I think you can get
> the 10" OTA for the same or less than the off axis reflector too.
> The mounted version comes on the SVP though. Isn't that more
> like an EQ5?

I can't stand it any more :-)

What are you talking about?

Chris