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Date: 11 Sep 2007 22:04:21
From: Macro
Subject: Coulter Telescopes
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Is the Coulter Company still around. And if so where is their website?
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Date: 12 Sep 2007 16:54:39
From: Dennis Woos
Subject: Re: Coulter Telescopes
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"Macro" <marcus.jesus@gmail.com > wrote in message
news:1189548261.099790.155090@22g2000hsm.googlegroups.com...
> Is the Coulter Company still around. And if so where is their website?
>
"part of Coulter Optical"
http://www.e-scopes.cc/
Our club has just completed a class where we walked 10 folks through
building 6" f/8 dobs using e-scope's kit, and the scopes are great. We
tested every mirror, and they all came in at least 1/8 wave. From our
experience, this is a great company.
Dennis
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Date: 11 Sep 2007 23:23:23
From: Shave Bush's Ass
Subject: Re: Coulter Telescopes
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Quadibloc wrote:
> Curtis Croulet wrote:
> > A friend of mine who is a professional optician says that one of Coulter's
> > problems was that they used unanealed glass. The Coulter scopes I've looked
> > through were enjoyable at 50x but not at 200x.
>
> I know that our local astronomy club had a 17" scope with a mirror
> from Coulter Optics, and the mirror was excellent. But it was stolen
> in a break-in; it was insured, but the replacement mirror was a
> disappointment.
>
> So there were apparently at least some very good mirrors, but I can
> see that something like that would impair consistency.
>
> John Savard
agree - our club's Coulter 17.5" is acceptably good optically.
Better than 1/4 wave and no tde. I dont know a person who
remounted their Coulter mirrors into a floation cell who wasnt
very happy. The Am Lunar society's archive shows some fabulous
lunar photos done with Coulters, which predictably people would
not believe. We have an old DS16 gem that I have seriously
thought about hoisting our Coulter on to with an appropriate
saddle. The tube is the old fashioned 'thick' 3/8 hardened
sonotube which time has shown to be very durable (and steady).
If there were a free 17" Coulter would it go unclaimed?
We have used our for years and like it but a floation mirror cell vastly improves
performance.
. . .
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Date: 12 Sep 2007 05:53:09
From: Curtis Croulet
Subject: Re: Coulter Telescopes
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Coulter gave a lot of value for the money.
--
Curtis Croulet
Temecula, California
33°27'59"N, 117°05'53"W
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Date: 13 Sep 2007 20:30:53
From: Johnny Borborigmi
Subject: Re: Coulter Telescopes
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On 2007-09-12 01:53:09 -0400, "Curtis Croulet"
<calypte@_NO_SPAM_verizon.net > said:
> Coulter gave a lot of value for the money.
Agreed, I had the 31.1" scope, GREAT views.
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Date: 11 Sep 2007 19:01:07
From: Quadibloc
Subject: Re: Coulter Telescopes
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Curtis Croulet wrote:
> A friend of mine who is a professional optician says that one of Coulter's
> problems was that they used unanealed glass. The Coulter scopes I've looked
> through were enjoyable at 50x but not at 200x.
I know that our local astronomy club had a 17" scope with a mirror
from Coulter Optics, and the mirror was excellent. But it was stolen
in a break-in; it was insured, but the replacement mirror was a
disappointment.
So there were apparently at least some very good mirrors, but I can
see that something like that would impair consistency.
John Savard
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Date: 11 Sep 2007 20:13:36
From: George
Subject: Re: Coulter Telescopes
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"Macro" <marcus.jesus@gmail.com > wrote in message
news:1189548261.099790.155090@22g2000hsm.googlegroups.com...
> Is the [Ann] Coulter Company still around. And if so where is their
> website?
More importantly, do their adds attack presidential candidates as being
homosexuals? lol
George
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Date: 11 Sep 2007 23:25:23
From: Shave Bush's Ass
Subject: Re: Coulter Telescopes
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Bag-Ann (the androgenous manic depressive) doesnt make scopes.
George wrote:
> "Macro" <marcus.jesus@gmail.com> wrote in message
> news:1189548261.099790.155090@22g2000hsm.googlegroups.com...
> > Is the [Ann] Coulter Company still around. And if so where is their
> > website?
>
> More importantly, do their adds attack presidential candidates as being
> homosexuals? lol
>
> George
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Date: 12 Sep 2007 02:19:06
From: George
Subject: Re: Coulter Telescopes
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"Shave Bush's Ass" <rodo@mchsi.com > wrote in message
news:46E76A33.B9B3667C@mchsi.com...
> Bag-Ann (the androgenous manic depressive) doesnt make scopes.
Yeah, well that makes sense. I guess it wouldn't be too confortable to sit
for long periods of time on such a boney arse.
George
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Date: 12 Sep 2007 01:55:02
From: Curtis Croulet
Subject: Re: Coulter Telescopes
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>> Is the [Ann] Coulter Company still around. And if so where is their
>> website?
>
> More importantly, do their adds attack presidential candidates as being
> homosexuals? lol
I know this is an attempt to be funny, but it's worth pointing out that
Coulter Optical was named for the Coulter pine (Pinus coulteri), which
occurs in the area.
--
Curtis Croulet
Temecula, California
33°27'59"N, 117°05'53"W
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Date: 12 Sep 2007 02:17:39
From: George
Subject: Re: Coulter Telescopes
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"Curtis Croulet" <calypte@_NO_SPAM_verizon.net > wrote in message
news:WFHFi.7185$He1.6883@trnddc03...
>>> Is the [Ann] Coulter Company still around. And if so where is their
>>> website?
>>
>> More importantly, do their adds attack presidential candidates as being
>> homosexuals? lol
>
> I know this is an attempt to be funny, but it's worth pointing out that
> Coulter Optical was named for the Coulter pine (Pinus coulteri), which
> occurs in the area.
> --
> Curtis Croulet
> Temecula, California
> 33°27'59"N, 117°05'53"W
I didn't know that. Thanks for the info. And yes, I was just trying to
inject some humour into the conversation. Sorry about that.
George
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Date: 11 Sep 2007 15:15:07
From: RMOLLISE
Subject: Re: Coulter Telescopes
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On Sep 11, 5:04 pm, Macro <marcus.je...@gmail.com > wrote:
> Is the Coulter Company still around. And if so where is their website?
No. Coulter (Jim Braginton's California company) went out of business
years ago. The name was sold to another firm, Murnaghan of Florida.
They produced a few Odysseys for a while, but only for a while. My
guess is they figgered (rightly) they could not compete with the other
players in the low-end dob biz.
There was some talk of them reviving the Odysseys a while back, but I
don't think anything ever came of it.
Jim Braginton's (Jacobson's) scopes were not fancy, and there optics
were not <ahem > top-notch, but he did turn a lot of folks on to the
deep sky in teh 80's and early 90s.
Unk Rod
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Date: 11 Sep 2007 22:41:41
From: Curtis Croulet
Subject: Re: Coulter Telescopes
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> No. Coulter (Jim Braginton's California company) went out of business
> years ago. The name was sold to another firm, Murnaghan of Florida.
> They produced a few Odysseys for a while, but only for a while. My
> guess is they figgered (rightly) they could not compete with the other
> players in the low-end dob biz.
>
> There was some talk of them reviving the Odysseys a while back, but I
> don't think anything ever came of it.
>
> Jim Braginton's (Jacobson's) scopes were not fancy, and there optics
> were not <ahem> top-notch, but he did turn a lot of folks on to the
> deep sky in teh 80's and early 90s.
A friend of mine who is a professional optician says that one of Coulter's
problems was that they used unanealed glass. The Coulter scopes I've looked
through were enjoyable at 50x but not at 200x. Coulter used to have demo
star parties at their plant in Idyllwild, CA, and I know he sold a lot of
scopes that way, and people seemed to be happy. This was at a time when
anything bigger than an 8-inch scope was a BIG scope and likely to be
extremely expensive, and people could be blown away by sheer light-gathering
power. I always swung by on a Sunday when no one was there, so I never had
a chance to go in the showroom or talk to anybody.
--
Curtis Croulet
Temecula, California
33°27'59"N, 117°05'53"W
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Date: 12 Sep 2007 05:55:19
From: David Knisely
Subject: Re: Coulter Telescopes
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Curtin Croulet posted:
> A friend of mine who is a professional optician says that one of Coulter's
> problems was that they used unanealed glass.
I don't think this was really the problem. Early on, the Coulter
mirrors tended to be fairly good (certainly better than 1/4 wave P-V on
the wavefront). I have an old 8 inch f/7 which I took right up to the
limits of seeing (well past 230x), so they did make a few good ones.
However, later on when demand for their Dob line increased, the quality
control took a real nosedive. I have an old Coulter 10 inch mirror that
was an absolute *dog*. It looked like two paraboloids of entirely
different focal lengths that met at the 65% zone! In the center of the
mirror was a large hole that looked like the crater Kepler, complete
with secondary impact pits :). Needless to say, the mirror gave lousy
views with severe spherical aberration. I had the mirror refigured by
Enterprise Optics, and they managed to straighten it out to nearly
1/20th wave (well, 1/19.6 wave if my Caustic tester is accurate), so it
now serves me quite well and I will probably never part with it. The
only good things about the experience were the final refigured mirror
and the fact that I finally learned how to test telescope mirrors.
Clear skies to you.
--
David W. Knisely KA0CZC@navix.net
Prairie Astronomy Club: http://www.prairieastronomyclub.org
Hyde Memorial Observatory: http://www.hydeobservatory.info/
**********************************************
* Attend the 14th Annual NEBRASKA STAR PARTY *
* July 15th-20th, 2007, Merritt Reservoir *
* http://www.NebraskaStarParty.org *
**********************************************
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Date: 12 Sep 2007 15:30:56
From: Curtis Croulet
Subject: Re: Coulter Telescopes
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> I don't think this was really the problem. Early on, the Coulter mirrors
> tended to be fairly good (certainly better than 1/4 wave P-V on the
> wavefront). I have an old 8 inch f/7 which I took right up to the limits
> of seeing (well past 230x), so they did make a few good ones. However,
> later on when demand for their Dob line increased, the quality control
> took a real nosedive. I have an old Coulter 10 inch mirror that was an
> absolute *dog*. It looked like two paraboloids of entirely different
> focal lengths that met at the 65% zone! In the center of the mirror was a
> large hole that looked like the crater Kepler, complete with secondary
> impact pits :). Needless to say, the mirror gave lousy views with severe
> spherical aberration. I had the mirror refigured by Enterprise Optics,
> and they managed to straighten it out to nearly 1/20th wave (well, 1/19.6
> wave if my Caustic tester is accurate), so it now serves me quite well and
> I will probably never part with it. The only good things about the
> experience were the final refigured mirror and the fact that I finally
> learned how to test telescope mirrors.
Coulter's mirrors were cut from sheets of unannealed soda-lime glass. Over
the years I've read a number of reports of good mirrors from Coulter, but it
seems to be more a matter of luck than consistent quality control. Whatever
the quality of the mirrors, their performance was compromised by the
near-impossibility of precision collimation. All of this is not a "knock,"
just a recognition of Coulter's goals with their scopes: low-power,
big-scope views of the deep-sky rather than APO-like views of planets. A
standard 12.5-inch Newtonian from, say, Parks (Cave was gone by then) cost,
what, $5K? A 13.1-inch from Coulter was $500, IIRC. A lot of people were
happy to go with Coulter and eschew the rare 300x views of Mars.
--
Curtis Croulet
Temecula, California
33°27'59"N, 117°05'53"W
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Date: 12 Sep 2007 15:40:50
From: David Knisely
Subject: Re: Coulter Telescopes
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Curtis Croulet posted:
> Coulter's mirrors were cut from sheets of unannealed soda-lime glass.
Well, my two Coulter mirrors were advertised to be Pyrex (and certainly
look to be that way), but both date back to the early 1970's, so perhaps
that changed. The soda-lime glass mirrors I have seen tend to have a
faint greenish cast to the sides when you look in, and both my primaries
are clear. In any case, simple glass can be used to make quality
telescope mirrors, although the methods may need to be changed slightly
to take into account the higher expansion coefficient of the simple
glass vs. Pyrex.
> Over
> the years I've read a number of reports of good mirrors from Coulter, but it
> seems to be more a matter of luck than consistent quality control.
Again, I have seen quite a number of good mirrors from Coulter, but
usually, they date back to before the Dobsonian era, when Coulter seemed
to be producing better optics. Of course, the Odyssey series of Coulter
Dobs were definitely made "on the cheap", especially in later years when
the big sky blue boxy Dobs were replaced by the more primitive red-tubed
models that had the altitude bearings mounted directly to the tube.
Clear skies to you.
--
David W. Knisely KA0CZC@navix.net
Prairie Astronomy Club: http://www.prairieastronomyclub.org
Hyde Memorial Observatory: http://www.hydeobservatory.info/
**********************************************
* Attend the 14th Annual NEBRASKA STAR PARTY *
* July 15th-20th, 2007, Merritt Reservoir *
* http://www.NebraskaStarParty.org *
**********************************************
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Date: 13 Sep 2007 02:21:18
From: Curtis Croulet
Subject: Re: Coulter Telescopes
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Of course, the Odyssey series of Coulter
> Dobs were definitely made "on the cheap", especially in later years when
> the big sky blue boxy Dobs were replaced by the more primitive red-tubed
> models that had the altitude bearings mounted directly to the tube.
I think there's probably a distinction between the separate optics and the
"Odyssey" scopes.
--
Curtis Croulet
Temecula, California
33°27'59"N, 117°05'53"W
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