Aftermarket v's Factory supplied mirrors

lal_truckee wrote:
Phil Wheeler wrote:


It may depend on the quality of the rest of the scope. It might make
sense to upgrade the elements of an otherwise premium Dob, but likely
would not for a more basic scope (e.g, Orion XT-10).


However, if one had the ambition to construct a high quality telescope
while also observing in the meantime, a "basic scope" gradually morphed
into that HQ scope might make sense provided one went into the process
recognizing that nothing would actually remain of the original scope(1).


Sure. But in Jan's case he is morphing a classic scope he first
acquired new 25 or so years ago.

I would not spend a lot of times upgrading a basic dob with metal tube
and particle board rocker box.

Phil

"Phil Wheeler" wrote in message
...
lal_truckee wrote:
Phil Wheeler wrote:


It may depend on the quality of the rest of the scope. It might make
sense to upgrade the elements of an otherwise premium Dob, but likely
would not for a more basic scope (e.g, Orion XT-10).


However, if one had the ambition to construct a high quality telescope
while also observing in the meantime, a "basic scope" gradually
morphed
into that HQ scope might make sense provided one went into the process
recognizing that nothing would actually remain of the original
scope(1).


Sure. But in Jan's case he is morphing a classic scope he first
acquired new 25 or so years ago.

I would not spend a lot of times upgrading a basic dob with metal tube
and particle board rocker box.

Phil

I tried to e-mail you a recent photo of the scope at it's latest "first
light" (with the new optics), but your e-mail address below wouldn't
accept it, or is bogus...

--
Jan Owen

To reach me directly, remove the Z, if one appears in my e-mail address...
Latitude: 33.6
Longitude: -112.3

I'd love to see it. Would you be so kind?

Errol
NOLA

would not spend a lot of times upgrading a basic dob with metal tube.

What are the HQ dobs made of if not metal? All the ones I've seen look
metal (in the magazines).

Starboard wrote:
would not spend a lot of times upgrading a basic dob with metal tube.


What are the HQ dobs made of if not metal? All the ones I've seen look
metal (in the magazines).



Usually sonotubes.

Some have trusses and no tube at all!

They are Not metal, there's planty of either snon tube or truss Dobs that
don't use metal tubes, don't just look at the big ads, look at some of the
smaller ads at names that make some people drool over.


--

The Lone Sidewalk Astronomer of Rosamond
Telescope Buyers FAQ
http://home.inreach.com/starlord
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http://www.cafepress.com/astronomy_net
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http://www.cafepress.com/ingarden
Blast Off Online Gift Shop
http://www.cafepress.com/starlords




"Starboard" wrote in message
ups.com...
would not spend a lot of times upgrading a basic dob with metal tube.

What are the HQ dobs made of if not metal? All the ones I've seen look
metal (in the magazines).

"Starboard" wrote in message
ups.com...
would not spend a lot of times upgrading a basic dob with metal tube.

What are the HQ dobs made of if not metal? All the ones I've seen look
metal (in the magazines).


In general terms, the highest quality Dobsonians today are of aluminum
truss designs, and not tubes at all (other than the aluminum truss tubes
used in the structure)... As close as these scopes come to tubes is
through the use of "light shrouds".

http://www.tscopes.com/FST/index.html

http://www.tscopes.com/

http://www.teeterstelescopes.com/planetkiller.html

http://www.teeterstelescopes.com/

http://www.starmastertelescopes.com/

http://www.mag1instruments.com/optics.html

Not a true *truss* tube design (in that the tubes are not triangulated,
but instead utilizes large tube diameter to compensate for the lack of
triangulation stiffness), but still:
http://www.plettstone.com/

--
Jan Owen

To reach me directly, remove the Z, if one appears in my e-mail address...
Latitude: 33.6
Longitude: -112.3

"Starboard" wrote in message
oups.com...
Part of a response (by Jan Owen) to one of my earlier post (1.25' v's
2" accessories) was:

I have completely refurbished this scope over the years, adding top
quality mirror cells, exquisite mirrors (primary by Mike Spooner,
certified secondary by Antares).

Is it common for experienced astronomers to change out their perfectly
good "stock" mirrors with "after-market" mirrors strictly for higher
performance? Jan states "top quality... exquisite mirrors." Are
Spooner mirrors better than stock mirrors or just good substitutes when
replacements are necessary; as was her situation?

E.g. swapping a perfectly good Rochester Quadrajet carburetor with a
Holly 750, or, a stock Fender pick-up with a Texas special... Just
curious...

Errol
NOLA


Last time I checked, I was a male. And I haven't had any surgery today...

And replacement of the Meade mirror wasn't a NECESSITY. I replaced the
optics as the final step in making this scope capable of delivering visual
images as good as physically possible for a scope of this size.

So... two incorrect assumptions right up front...

For folks who know, use, and appreciate fine optics, there is a difference
between factory standard mirrors, and nearly perfect mirrors made by fine
craftsmen, though to the inexperienced observer, there may be no obvious
difference. It IS possible for a factory mirror to approach perfection.
But it doesn't happen all the time. The vast majority of mirrors coming
from the various OEM makers will do a very nice job for most of their
customers. Not an EXQUISITE job, but a very good job.

Some folks CAN tell the difference, and others probably never will...
Meade parabolic mirrors made in their Irvine facility, have generally been
quite good over the years, and my experience with Meade goes back over 25
years. There have been a (very) few that were not. The one I replaced
was quite good. I also have an Orion mirror for this scope that was made
by Discovery Telescopes back when they made Orion's scopes. IT is quite
good. Both of these mirrors are (still) about as good as you could hope
from semi-production line scope mirrors.

But there's another group of mirror makers whose specialty is directed
solely at making mirrors for folks who know how good mirrors CAN be, and
they make mirrors for those folks, who will gladly pay commensurate with
their quality. Carl Zambuto is one of those. So is Mike Spooner. There
are several others.

After you have been at this for awhile, you will understand.

--
Jan Owen

To reach me directly, remove the Z, if one appears in my e-mail address...
Latitude: 33.6
Longitude: -112.3

Testy... (I swear, no pun intended)

Well, your choice word was "refurbished". According to my dictionary,
in short means "to clean, brighten, or renovate." Since you changed the
mirror, you didn't clean or brighten. You must have renovated. Now,
"renovate", according to same, means to restore by repair or..... Never
mind....

As for assuming "Jan" was a girls name, I apologize and stand
corrected... Please don't linger on it too long...

Errol
NOLA

"Starboard" wrote in message
ups.com...
Testy... (I swear, no pun intended)

Well, your choice word was "refurbished". According to my dictionary,
in short means "to clean, brighten, or renovate." Since you changed the
mirror, you didn't clean or brighten. You must have renovated. Now,
"renovate", according to same, means to restore by repair or..... Never
mind....

As for assuming "Jan" was a girls name, I apologize and stand
corrected... Please don't linger on it too long...

Errol
NOLA


I did use the term refurbish. And some of that was what I did... I
replaced, or upgraded, if you will, some of the lesser parts (focuser -
TWICE, spider and secondary holder, primary cell - but ended up moving
back to the original, and added a 9X60 finder in place of the original),
and then replaced some of the replacements, when even BETTER parts became
available (there have been many opportunities for this; this scope is 25
years old).

I bought the Orion mirror because I was hearing good things about their
mirrors, and it IS a good mirror, but not better than the original. And a
very good mirror was not in keeping with my objectives in upgrading &
customizing this scope. A top level mirror and an exceptional secondary
that would not degrade the image from the primary was what I was looking
for, and what I now have... And eyepieces that complement the rest.

It's a disease that strikes folks in this hobby... Some worse than
others. It's related to aperture fever, but somewhat different, too...
I've also been guilty of aperture fever, and have the scopes (and have had
even more) to prove it... The scope in question is my second smallest.

All these things come with due time in the hobby... And after enough
time, when your body simply can't deal with the size and weight anymore,
sanity returns, though slowly, and you again begin to be a little bit (a
LITTLE bit) more practical... And the quest for the best optics begins to
dim a little eventually, as your vision begins to deteriorate with age.
I'm just beginning to reach that threshold now...

Perhaps in your case, you are being more practical on the FRONT end... If
so, and you never get the FEVER, congratulations!

--
Jan Owen

To reach me directly, remove the Z, if one appears in my e-mail address...
Latitude: 33.6
Longitude: -112.3