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  • Members: 2394
  • Category: Amateur
  • Founded: Jun 20, 2000
  • Language: English
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#19972 From: "William L" <williebluestar@...>
Date: Mon Jun 6, 2011 5:17 pm
Subject: Re: Vetter
williebluestar
Send Email Send Email
 
No Idea how a message meant for another group ended up here.

VERY STRANGE!

WB*

--- In bigdob@yahoogroups.com, William Blakeslee <williebluestar@...> wrote:
>
> 4. OMG- What a Beautiful Scooter
>     Posted by: "Dave" ocartprof@... ocartprof
>     Date: Wed May 25, 2011 7:31 pm ((PDT))
>
>
> Craig Vetter is (was?)  an interesting guy. Best known for his
>
>
> [Non-text portions of this message have been removed]
>

#19973 From: "Neal Galt" <neal@...>
Date: Tue Jun 7, 2011 12:56 am
Subject: Re: Re: Vetter
nealgalt
Send Email Send Email
 
It's the new biker star party!?????
   ----- Original Message -----
   From: William L
   To: bigdob@yahoogroups.com
   Sent: Monday, June 06, 2011 10:17 AM
   Subject: [bigdob] Re: Vetter



   No Idea how a message meant for another group ended up here.

   VERY STRANGE!

   WB*

   --- In bigdob@yahoogroups.com, William Blakeslee <williebluestar@...> wrote:
   >
   > 4. OMG- What a Beautiful Scooter
   >     Posted by: "Dave" ocartprof@... ocartprof
   >     Date: Wed May 25, 2011 7:31 pm ((PDT))
   >
   >
   > Craig Vetter is (was?)  an interesting guy. Best known for his
   >
   >
   > [Non-text portions of this message have been removed]
   >





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

#19974 From: "Joe" <kc5mip@...>
Date: Thu Jun 16, 2011 6:25 pm
Subject: 13.1 colter mirror need data on 9 point cell
kc5mip
Send Email Send Email
 
I have a 13.1 telescope which someone had glud the whole mirror on a flat
support . ya right ! that what I have and I need the data for a 18 or 9 point
flotation cell for my 13.1  F4.5  so I would appreciate help on this project .
:)

#19975 From: John Mahony <jmmahony@...>
Date: Thu Jun 16, 2011 7:12 pm
Subject: Re: 13.1 colter mirror need data on 9 point cell
jmmahony
Send Email Send Email
 
----- Original Message ----

> From: Joe <kc5mip@...>
>
> I have a 13.1 telescope which someone had glud the whole mirror on a flat
>support . ya right !

That's how Coulter made them ;)

> that what I have and I need the data for a 18 or 9 point  flotation cell for
my
>13.1  F4.5  so I would appreciate help on this  project . :)
>
>

Use the program "Plop":
<http://www.davidlewistoronto.com/plop/>

Details (for a given # of support points) will vary slightly depending on the
mirror thickness and f ratio, but if you want a generic answer, you might find
it here:
<http://www.davidlewistoronto.com/plop/design.htm>

-John

#19976 From: "Nils Olof Carlin" <nilsolof.carlin@...>
Date: Thu Jun 16, 2011 7:21 pm
Subject: Re: 13.1 colter mirror need data on 9 point cell
nilsolofcarlin
Send Email Send Email
 
Joe,

a 6 point cell is perfectly adequate (I use it for my Coulter 13.1), simpler
and actually better than a 9 pt cell (18 is overkill!).
The supports are at 60% of the radius. BTW the deformation is a tad less
than 2.5 nm RMS.

Nils Olof


----- Original Message -----
From: "Joe" <kc5mip@...>
To: <bigdob@yahoogroups.com>
Sent: Thursday, June 16, 2011 8:25 PM
Subject: [bigdob] 13.1 colter mirror need data on 9 point cell


>I have a 13.1 telescope which someone had glud the whole mirror on a flat
>support . ya right ! that what I have and I need the data for a 18 or 9
>point flotation cell for my 13.1  F4.5  so I would appreciate help on this
>project . :)
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
>

#19977 From: Stephen Koehler <s.c.koehler@...>
Date: Thu Jun 16, 2011 7:36 pm
Subject: Re: 13.1 colter mirror need data on 9 point cell
steve_koehler
Send Email Send Email
 
Joe,

I have a 13.1 telescope which someone had glud the whole mirror on a flat
> support . ya right ! that what I have and I need the data for a 18 or 9
> point flotation cell for my 13.1  F4.5  so I would appreciate help on this
> project . :)
>

Mark Holm has collected data for a lot of different cell designs for
different size mirrors.  In many of the tables he has the Coulter 13.1"
mirror listed.  You actually only need 6 points for your purpose.  Here's a
link to the top page and to the page of 6-point cells:

http://www.atmsite.org/contrib/Holm/Plop_optimized_cells/index.html
http://www.atmsite.org/contrib/Holm/Plop_optimized_cells/6point.html

I forget the thickness of the coulter mirrors, but he lists a 1" thick f/4.4
and a 1.5" thick f/4.5.  The latter has a P-V error of 1/64 wave for the
6-point cell.
--
Steve Koehler


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

#19978 From: "Joe" <kc5mip@...>
Date: Fri Jun 24, 2011 5:52 pm
Subject: I seem to cant figure out the the Holm plop for 6 point mirror cell for 13.1
kc5mip
Send Email Send Email
 
on page 1 of 3 for the 6 point it say  R1+ 0.517  is this data all in MM and
this being the mirror pivot point I measure and it almost is out of the mirror
diameter for the 13.1 or 332.74 / I am not that good in math so there where I am
right now . I cant seem to find a site that just give the info like the pivot
point  and the out data for the bear for all 3 mirror suppers.

#19979 From: Stephen Koehler <s.c.koehler@...>
Date: Fri Jun 24, 2011 6:57 pm
Subject: Re: I seem to cant figure out the the Holm plop for 6 point mirror cell for 13.1
steve_koehler
Send Email Send Email
 
Joe,

In inches, the distance from the center of the mirror to the three support
points for the bars is r1*Diameter/2 = 3.39 inches (86.1 mm).  The distance
between the support points on the bars is d*Diameter/2 = 3.91 inches (99.2
mm).

On Fri, Jun 24, 2011 at 12:52 PM, Joe <kc5mip@...> wrote:

> on page 1 of 3 for the 6 point it say  R1+ 0.517  is this data all in MM
> and this being the mirror pivot point I measure and it almost is out of the
> mirror diameter for the 13.1 or 332.74 / I am not that good in math so there
> where I am right now . I cant seem to find a site that just give the info
> like the pivot point  and the out data for the bear for all 3 mirror
> suppers.
>

--
Steve Koehler


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

#19980 From: "Joe" <kc5mip@...>
Date: Fri Jun 24, 2011 9:36 pm
Subject: Re: I seem to cant figure out the the Holm plop for 6 point mirror cell for 13.1
kc5mip
Send Email Send Email
 
thank . after I sent this to you my friend came over to make a point of I did
not consider fractions  . I am 64 and more slow this days and not like I was
when I was young . strange that 13.1 telescope seem to be getting heavier as I
get old so I am re-designing to brake down EZ. :) clear sky`s to all.

--- In bigdob@yahoogroups.com, Stephen Koehler <s.c.koehler@...> wrote:
>
> Joe,
>
> In inches, the distance from the center of the mirror to the three support
> points for the bars is r1*Diameter/2 = 3.39 inches (86.1 mm).  The distance
> between the support points on the bars is d*Diameter/2 = 3.91 inches (99.2
> mm).
>
> On Fri, Jun 24, 2011 at 12:52 PM, Joe <kc5mip@...> wrote:
>
> > on page 1 of 3 for the 6 point it say  R1+ 0.517  is this data all in MM
> > and this being the mirror pivot point I measure and it almost is out of the
> > mirror diameter for the 13.1 or 332.74 / I am not that good in math so there
> > where I am right now . I cant seem to find a site that just give the info
> > like the pivot point  and the out data for the bear for all 3 mirror
> > suppers.
> >
>
> --
> Steve Koehler
>
>
> [Non-text portions of this message have been removed]
>

#19981 From: "Art Russell" <russell_art@...>
Date: Sat Jun 25, 2011 12:38 pm
Subject: Re: Adaptive optics
art2001_30307
Send Email Send Email
 
Dick,

So untrue.  There are a few of us visitors that are still using the Mark I
Eyeball, albeit a bit aged, instead of those new fangled electronic viewing
devices. Moreover, in my opinion, there are many views that can only be
appreciated at the eyepiece.

Cheers,

Art

--- In bigdob@yahoogroups.com, "Dick" <rmcarner@...> wrote:
>
>
>
>
> --- In bigdob@yahoogroups.com, "Fabio" <cielobuio@> wrote:
> >
> > Dear all,
> > When I first heard of AO, in the early '90, I thought that in around 10
years it would be available to amateurs too. For the CCD it took 10 year from
laboratory (early '70) to professionals (early '80) and another 10 to get to the
amateurs (late '80- early '90). Now are already 20 years that professionals
works on and with AO (the military: 40 years?).
> > All will agree with me that seeing Jupiter or Saturn directly through
> > the eyepiece is, by far, more satisfying than seeing them on a PC
> > screen. Amateurs are forced to use webcams and CCDs to overcome the
> > blurring of our atmosphere. If it was available a good AO system a lot
> > of them will come back to visual observing.
>
> Maybe. Maybe not. Over the past 10 years, I have observed with a gang down in
a place called Chiefland, Florida. It's a place where most folks who live there
pronounce Italians 'Eyetalians'. There is even an 'Eyetalian' restaurant of
sorts although you might not recognize the food as such... Back to the topic at
hand. Seeing in Chiefland can be pretty good since it is within 15 miles of the
Gulf of Mexico. On occasion and only rarely can I induce this bunch to step out
of their collective bunker, away from their bank of computer screens in order to
look at the Veil or Jupiter in real time. So, I don't think it is so much an
issue - as you put it that: 'Amateurs are forced to use webcams and CCDs to
overcome the blurring of our atmosphere.'And, consequently they would revert
[back] to...gasp looking through an eyepiece if AO was available. I can tell you
first hand that this bunches passion is a)finding the appropriate object for the
size of their camera (alas they are running out of objects), b) finding an
appropriate guide star, c) getting in their 'runs' before the clouds come over,
and d)recreating the image in Photoshop.
> Snip..
> > How much would you pay for an AO system that will allow you to see directly,
with your eye(s), Mars, Jupiter and Saturn like if you're in space with your 30"
scope?
>
> I'm still saving up for my next mirror - a 28". -:)
> Dick
>

#19982 From: "Dick" <rmcarner@...>
Date: Sat Jun 25, 2011 1:26 pm
Subject: Re: Adaptive optics
rmcarner
Send Email Send Email
 
--- In bigdob@yahoogroups.com, "Art Russell" <russell_art@...> wrote:

> Dick,
> So untrue.  There are a few of us visitors that are still using the Mark I
Eyeball, albeit a bit aged, instead of those new fangled electronic viewing
devices. Moreover, in my opinion, there are many views that can only be
appreciated at the eyepiece.

So true.. Art, I don't think you meant this response for me. My message (below)
was intended to convey the sentiment that I enjoy viewing objects the old
fashion way - through an eyepiece.
Dick

> > --- In bigdob@yahoogroups.com, "Fabio" <cielobuio@> wrote:
> > >
> > > Dear all,
> > > When I first heard of AO, in the early '90, I thought that in around 10
years it would be available to amateurs too. For the CCD it took 10 year from
laboratory (early '70) to professionals (early '80) and another 10 to get to the
amateurs (late '80- early '90). Now are already 20 years that professionals
works on and with AO (the military: 40 years?).
> > > All will agree with me that seeing Jupiter or Saturn directly through
> > > the eyepiece is, by far, more satisfying than seeing them on a PC
> > > screen. Amateurs are forced to use webcams and CCDs to overcome the
> > > blurring of our atmosphere. If it was available a good AO system a lot
> > > of them will come back to visual observing.
And Dick wrote..
> > Maybe. Maybe not. Over the past 10 years, I have observed with a gang down
in a place called Chiefland, Florida. It's a place where most folks who live
there pronounce Italians 'Eyetalians'. There is even an 'Eyetalian' restaurant
of sorts although you might not recognize the food as such... Back to the topic
at hand. Seeing in Chiefland can be pretty good since it is within 15 miles of
the Gulf of Mexico. On occasion and only rarely can I induce this bunch to step
out of their collective bunker, away from their bank of computer screens in
order to look at the Veil or Jupiter in real time. So, I don't think it is so
much an issue - as you put it that: 'Amateurs are forced to use webcams and CCDs
to overcome the blurring of our atmosphere.'And, consequently they would revert
[back] to...gasp looking through an eyepiece if AO was available. I can tell you
first hand that this bunches passion is a)finding the appropriate object for the
size of their camera (alas they are running out of objects), b) finding an
appropriate guide star, c) getting in their 'runs' before the clouds come over,
and d)recreating the image in Photoshop.
> > Snip..
> > > How much would you pay for an AO system that will allow you to see
directly, with your eye(s), Mars, Jupiter and Saturn like if you're in space
with your 30" scope?
> >
> > I'm still saving up for my next mirror - a 28". -:)
> > Dick
> >
>

#19983 From: "tsulmer1" <timulmer@...>
Date: Mon Jun 27, 2011 4:43 am
Subject: Cleaning Telescope Mirror with Steam
tsulmer1
Send Email Send Email
 
I know the "usual" method for cleaning our mirrors:  soap in warm water with a
couple drops of dove dish soap for 15 minutes, use a soft cotton cloth or cotton
balls and gentle clean (using no pressure and constantly moving to a clean
cotton ball or clean part of the cloth).  Then rinse with distilled water and
put on its side to dry.  I also blow it off with Aargon gas.

But for really caked on grime (pollens, etc.), you have to scrub and then come
the scratches.

So, I have an idea....Use the inexpensive steam cleaners you can buy at most
department stores.  They blow hot steam under pressure to dislodge grime. 
People use them to clean toilets, stoves, etc.

Anyone ever try this?  Anything to be concerned about?  I've put my hand in the
path of the steam and it is hot but not scalding until you get very very close
to the nozzle.  My idea is to start further away and let the lower temp and
pressure work on the grime and slowly move closer (i.e. hot and more pressure)
for really stubborn grime.
But before I give it a go, I thought I canvas the collective experience of the
group.  (I'm a little concerned about the coatings if I get to much heat and
pressure.)

Anyone?

Thanks, Tim in Calgary

#19984 From: Roger Greenwood <roger@...>
Date: Mon Jun 27, 2011 11:34 am
Subject: Re: Cleaning Telescope Mirror with Steam
astrocrumb
Send Email Send Email
 
Tim,

I have never considered steam, but if you are using distilled water, and the
steamer isn't introducing
any foreign matter from a cheap steamer, it might be OK. But I thought steam
cleaning involved a lot of
pressure when cleaning those items you mentioned. I would be a little concerned
if it was steam and
pressure. This might be reinventing the wheel straying from the traditional
materials.

I would like to mention my technique for cleaning as it does remove all matter,
pollen, dust
from years of buildup, etc. with the usual materials.

1. Stand mirror up on edge(I leave it in the mirror box with towels to soak up
run-off)
2. Rinse with a strong stream of the distilled soapy water from a squirty
bottle(not a spray bottle)
3. Take a 3" x 5" piece of cotton cut from a sterile cotton roll and soak it
with the soapy
     water from the squirty bottle and with two hands draw it across the mirror,
rolling it gently away
     to lift off all dirt. Then hit mirror with soapy water from the soapy bottle
again. I do this accross
     the mirror overlapping the passes by 50% each time. Cut a fresh piece of
cotton for every pass.
4. Rinse with distilled water from another squiirty bottle.

I've washed my 18" mirror twice a year with this technique for 10 years and
never had a scratch.
I also wash friends mirrors with the same results.

-Roger
18" Obsession SC/AN/FSA
www.astrocrumb.com

On Jun 27, 2011, at 12:43 AM, tsulmer1 wrote:

> I know the "usual" method for cleaning our mirrors:  soap in warm water with a
couple drops of dove dish soap for 15 minutes, use a soft cotton cloth or cotton
balls and gentle clean (using no pressure and constantly moving to a clean
cotton ball or clean part of the cloth).  Then rinse with distilled water and
put on its side to dry.  I also blow it off with Aargon gas.
>
> But for really caked on grime (pollens, etc.), you have to scrub and then come
the scratches.
>
> So, I have an idea....Use the inexpensive steam cleaners you can buy at most
department stores.  They blow hot steam under pressure to dislodge grime. 
People use them to clean toilets, stoves, etc.
>
> Anyone ever try this?  Anything to be concerned about?  I've put my hand in
the path of the steam and it is hot but not scalding until you get very very
close to the nozzle.  My idea is to start further away and let the lower temp
and pressure work on the grime and slowly move closer (i.e. hot and more
pressure) for really stubborn grime.
> But before I give it a go, I thought I canvas the collective experience of the
group.  (I'm a little concerned about the coatings if I get to much heat and
pressure.)
>
> Anyone?
>
> Thanks, Tim in Calgary
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>

#19985 From: "paul_winalski" <Prune@...>
Date: Mon Jun 27, 2011 4:22 pm
Subject: Re: Cleaning Telescope Mirror with Steam
paul_winalski
Send Email Send Email
 
I'd make sure that whatever substance is used for the mirror coating doesn't
react with steam.  There are substances that are inert when exposed to liquid
water that will react with steam.

Clear skies,

-Paul W.

#19986 From: SCOTT BEARD <indianola@...>
Date: Mon Jun 27, 2011 8:32 pm
Subject: Re: Cleaning Telescope Mirror with Steam
scott_beard2000
Send Email Send Email
 
I would be VERY cautious about the temperature.
In the mirror making class I took, we always washed with room temperature water.
Most mirror cleaning articles I've read specifically say to use room temperature
water.
Personally, I wouldn't risk using a steamer.  The down-side consequence if
something went wrong is too great compared to any benefit.

But if I were in crazy enough mood to try it, I would at least put a spacer on
the front of the steamer, so that I couldn't get it too close.
(I'm the sort that would be so focued on removing the spot, that I wouldn't
notice that I slowly got the steamer too close.)

I think by the time you get the steamer far enough away, to not risk breaking
your mirror due to thermal shock, you may not be getting any benefit from the
steamer.

Scott Beard




________________________________
From: tsulmer1 <timulmer@...>
To: bigdob@yahoogroups.com
Sent: Sun, June 26, 2011 9:43:52 PM
Subject: [bigdob] Cleaning Telescope Mirror with Steam

 
I know the "usual" method for cleaning our mirrors: soap in warm water with a
couple drops of dove dish soap for 15 minutes, use a soft cotton cloth or cotton
balls and gentle clean (using no pressure and constantly moving to a clean
cotton ball or clean part of the cloth). Then rinse with distilled water and put
on its side to dry. I also blow it off with Aargon gas.

But for really caked on grime (pollens, etc.), you have to scrub and then come
the scratches.


So, I have an idea....Use the inexpensive steam cleaners you can buy at most
department stores. They blow hot steam under pressure to dislodge grime. People
use them to clean toilets, stoves, etc.


Anyone ever try this? Anything to be concerned about? I've put my hand in the
path of the steam and it is hot but not scalding until you get very very close
to the nozzle. My idea is to start further away and let the lower temp and
pressure work on the grime and slowly move closer (i.e. hot and more pressure)
for really stubborn grime.

But before I give it a go, I thought I canvas the collective experience of the
group. (I'm a little concerned about the coatings if I get to much heat and
pressure.)

Anyone?

Thanks, Tim in Calgary




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

#19987 From: "Joe" <kc5mip@...>
Date: Tue Jun 28, 2011 12:36 pm
Subject: Re: Cleaning Telescope Mirror with Steam
kc5mip
Send Email Send Email
 
At McDonald Observatory in west Texas I got to see how they use  Co2 to clean
the mirror of the there new Eberly telescope

--- In bigdob@yahoogroups.com, Roger Greenwood <roger@...> wrote:
>
> Tim,
>
> I have never considered steam, but if you are using distilled water, and the
steamer isn't introducing
> any foreign matter from a cheap steamer, it might be OK. But I thought steam
cleaning involved a lot of
> pressure when cleaning those items you mentioned. I would be a little
concerned if it was steam and
> pressure. This might be reinventing the wheel straying from the traditional
materials.
>
> I would like to mention my technique for cleaning as it does remove all
matter, pollen, dust
> from years of buildup, etc. with the usual materials.
>
> 1. Stand mirror up on edge(I leave it in the mirror box with towels to soak up
run-off)
> 2. Rinse with a strong stream of the distilled soapy water from a squirty
bottle(not a spray bottle)
> 3. Take a 3" x 5" piece of cotton cut from a sterile cotton roll and soak it
with the soapy
>     water from the squirty bottle and with two hands draw it across the
mirror, rolling it gently away
>     to lift off all dirt. Then hit mirror with soapy water from the soapy
bottle again. I do this accross
>     the mirror overlapping the passes by 50% each time. Cut a fresh piece of
cotton for every pass.
> 4. Rinse with distilled water from another squiirty bottle.
>
> I've washed my 18" mirror twice a year with this technique for 10 years and
never had a scratch.
> I also wash friends mirrors with the same results.
>
> -Roger
> 18" Obsession SC/AN/FSA
> www.astrocrumb.com
>
> On Jun 27, 2011, at 12:43 AM, tsulmer1 wrote:
>
> > I know the "usual" method for cleaning our mirrors:  soap in warm water with
a couple drops of dove dish soap for 15 minutes, use a soft cotton cloth or
cotton balls and gentle clean (using no pressure and constantly moving to a
clean cotton ball or clean part of the cloth).  Then rinse with distilled water
and put on its side to dry.  I also blow it off with Aargon gas.
> >
> > But for really caked on grime (pollens, etc.), you have to scrub and then
come the scratches.
> >
> > So, I have an idea....Use the inexpensive steam cleaners you can buy at most
department stores.  They blow hot steam under pressure to dislodge grime. 
People use them to clean toilets, stoves, etc.
> >
> > Anyone ever try this?  Anything to be concerned about?  I've put my hand in
the path of the steam and it is hot but not scalding until you get very very
close to the nozzle.  My idea is to start further away and let the lower temp
and pressure work on the grime and slowly move closer (i.e. hot and more
pressure) for really stubborn grime.
> > But before I give it a go, I thought I canvas the collective experience of
the group.  (I'm a little concerned about the coatings if I get to much heat and
pressure.)
> >
> > Anyone?
> >
> > Thanks, Tim in Calgary
> >
> >
> >
> > ------------------------------------
> >
> > Yahoo! Groups Links
> >
> >
> >
>

#19988 From: Tim Ulmer <timulmer@...>
Date: Tue Jun 28, 2011 3:21 pm
Subject: RE: Re: Cleaning Telescope Mirror with Steam
tsulmer1
Send Email Send Email
 
How did they do it?

Tim

________________________________
From: bigdob@yahoogroups.com [mailto:bigdob@yahoogroups.com] On Behalf Of Joe
Sent: Tuesday, June 28, 2011 6:37 AM
To: bigdob@yahoogroups.com
Subject: [bigdob] Re: Cleaning Telescope Mirror with Steam



At McDonald Observatory in west Texas I got to see how they use Co2 to clean the
mirror of the there new Eberly telescope

--- In bigdob@yahoogroups.com<mailto:bigdob%40yahoogroups.com>, Roger Greenwood
<roger@...> wrote:
>
> Tim,
>
> I have never considered steam, but if you are using distilled water, and the
steamer isn't introducing
> any foreign matter from a cheap steamer, it might be OK. But I thought steam
cleaning involved a lot of
> pressure when cleaning those items you mentioned. I would be a little
concerned if it was steam and
> pressure. This might be reinventing the wheel straying from the traditional
materials.
>
> I would like to mention my technique for cleaning as it does remove all
matter, pollen, dust
> from years of buildup, etc. with the usual materials.
>
> 1. Stand mirror up on edge(I leave it in the mirror box with towels to soak up
run-off)
> 2. Rinse with a strong stream of the distilled soapy water from a squirty
bottle(not a spray bottle)
> 3. Take a 3" x 5" piece of cotton cut from a sterile cotton roll and soak it
with the soapy
> water from the squirty bottle and with two hands draw it across the mirror,
rolling it gently away
> to lift off all dirt. Then hit mirror with soapy water from the soapy bottle
again. I do this accross
> the mirror overlapping the passes by 50% each time. Cut a fresh piece of
cotton for every pass.
> 4. Rinse with distilled water from another squiirty bottle.
>
> I've washed my 18" mirror twice a year with this technique for 10 years and
never had a scratch.
> I also wash friends mirrors with the same results.
>
> -Roger
> 18" Obsession SC/AN/FSA
> www.astrocrumb.com
>
> On Jun 27, 2011, at 12:43 AM, tsulmer1 wrote:
>
> > I know the "usual" method for cleaning our mirrors: soap in warm water with
a couple drops of dove dish soap for 15 minutes, use a soft cotton cloth or
cotton balls and gentle clean (using no pressure and constantly moving to a
clean cotton ball or clean part of the cloth). Then rinse with distilled water
and put on its side to dry. I also blow it off with Aargon gas.
> >
> > But for really caked on grime (pollens, etc.), you have to scrub and then
come the scratches.
> >
> > So, I have an idea....Use the inexpensive steam cleaners you can buy at most
department stores. They blow hot steam under pressure to dislodge grime. People
use them to clean toilets, stoves, etc.
> >
> > Anyone ever try this? Anything to be concerned about? I've put my hand in
the path of the steam and it is hot but not scalding until you get very very
close to the nozzle. My idea is to start further away and let the lower temp and
pressure work on the grime and slowly move closer (i.e. hot and more pressure)
for really stubborn grime.
> > But before I give it a go, I thought I canvas the collective experience of
the group. (I'm a little concerned about the coatings if I get to much heat and
pressure.)
> >
> > Anyone?
> >
> > Thanks, Tim in Calgary
> >
> >
> >
> > ------------------------------------
> >
> > Yahoo! Groups Links
> >
> >
> >
>



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

#19989 From: Jim Chandler <jimchandler@...>
Date: Tue Jun 28, 2011 3:47 pm
Subject: Re: Re: Cleaning Telescope Mirror with Steam
jimcchandler
Send Email Send Email
 
They release liquid CO2 through a cylindrical wand. As it expands, it
turns into CO2 snow, which knocks the dust off the mirrors. The snow
rapidly sublimes, thanks to the low humidity, leaving no mess.

This technique must be used frequently to be effective, as it only
removes loose dust, not anything actually stuck to the mirrors.
Waterspots, oil, and dust & pollen that have been on the mirror long
enough to have adhered aren't affected by the snow.

Jim

On 6/28/2011 10:21 AM, Tim Ulmer wrote:
>
> How did they do it?
>
> Tim
>
> ________________________________
> From: bigdob@yahoogroups.com <mailto:bigdob%40yahoogroups.com>
> [mailto:bigdob@yahoogroups.com <mailto:bigdob%40yahoogroups.com>] On
> Behalf Of Joe
> Sent: Tuesday, June 28, 2011 6:37 AM
> To: bigdob@yahoogroups.com <mailto:bigdob%40yahoogroups.com>
> Subject: [bigdob] Re: Cleaning Telescope Mirror with Steam
>
> At McDonald Observatory in west Texas I got to see how they use Co2 to
> clean the mirror of the there new Eberly telescope
>
> --- In bigdob@yahoogroups.com
> <mailto:bigdob%40yahoogroups.com><mailto:bigdob%40yahoogroups.com>,
> Roger Greenwood <roger@...> wrote:
> >
> > Tim,
> >
> > I have never considered steam, but if you are using distilled water,
> and the steamer isn't introducing
> > any foreign matter from a cheap steamer, it might be OK. But I
> thought steam cleaning involved a lot of
> > pressure when cleaning those items you mentioned. I would be a
> little concerned if it was steam and
> > pressure. This might be reinventing the wheel straying from the
> traditional materials.
> >
> > I would like to mention my technique for cleaning as it does remove
> all matter, pollen, dust
> > from years of buildup, etc. with the usual materials.
> >
> > 1. Stand mirror up on edge(I leave it in the mirror box with towels
> to soak up run-off)
> > 2. Rinse with a strong stream of the distilled soapy water from a
> squirty bottle(not a spray bottle)
> > 3. Take a 3" x 5" piece of cotton cut from a sterile cotton roll and
> soak it with the soapy
> > water from the squirty bottle and with two hands draw it across the
> mirror, rolling it gently away
> > to lift off all dirt. Then hit mirror with soapy water from the
> soapy bottle again. I do this accross
> > the mirror overlapping the passes by 50% each time. Cut a fresh
> piece of cotton for every pass.
> > 4. Rinse with distilled water from another squiirty bottle.
> >
> > I've washed my 18" mirror twice a year with this technique for 10
> years and never had a scratch.
> > I also wash friends mirrors with the same results.
> >
> > -Roger
> > 18" Obsession SC/AN/FSA
> > www.astrocrumb.com
> >
> > On Jun 27, 2011, at 12:43 AM, tsulmer1 wrote:
> >
> > > I know the "usual" method for cleaning our mirrors: soap in warm
> water with a couple drops of dove dish soap for 15 minutes, use a soft
> cotton cloth or cotton balls and gentle clean (using no pressure and
> constantly moving to a clean cotton ball or clean part of the cloth).
> Then rinse with distilled water and put on its side to dry. I also
> blow it off with Aargon gas.
> > >
> > > But for really caked on grime (pollens, etc.), you have to scrub
> and then come the scratches.
> > >
> > > So, I have an idea....Use the inexpensive steam cleaners you can
> buy at most department stores. They blow hot steam under pressure to
> dislodge grime. People use them to clean toilets, stoves, etc.
> > >
> > > Anyone ever try this? Anything to be concerned about? I've put my
> hand in the path of the steam and it is hot but not scalding until you
> get very very close to the nozzle. My idea is to start further away
> and let the lower temp and pressure work on the grime and slowly move
> closer (i.e. hot and more pressure) for really stubborn grime.
> > > But before I give it a go, I thought I canvas the collective
> experience of the group. (I'm a little concerned about the coatings if
> I get to much heat and pressure.)
> > >
> > > Anyone?
> > >
> > > Thanks, Tim in Calgary
> > >
> > >
> > >
> > > ------------------------------------
> > >
> > > Yahoo! Groups Links
> > >
> > >
> > >
> >
>
> [Non-text portions of this message have been removed]
>
>

#19990 From: Tim Ulmer <timulmer@...>
Date: Wed Jun 29, 2011 1:56 am
Subject: RE: Cleaning Telescope Mirror with Steam
tsulmer1
Send Email Send Email
 
Thanks to everyone for the responses. Greatly appreciatede.

Tim in Calgary
________________________________
From: bigdob@yahoogroups.com [bigdob@yahoogroups.com] On Behalf Of SCOTT BEARD
[indianola@...]
Sent: Monday, June 27, 2011 2:32 PM
To: bigdob@yahoogroups.com
Subject: Re: [bigdob] Cleaning Telescope Mirror with Steam



I would be VERY cautious about the temperature.
In the mirror making class I took, we always washed with room temperature water.
Most mirror cleaning articles I've read specifically say to use room temperature
water.
Personally, I wouldn't risk using a steamer.  The down-side consequence if
something went wrong is too great compared to any benefit.

But if I were in crazy enough mood to try it, I would at least put a spacer on
the front of the steamer, so that I couldn't get it too close.
(I'm the sort that would be so focued on removing the spot, that I wouldn't
notice that I slowly got the steamer too close.)

I think by the time you get the steamer far enough away, to not risk breaking
your mirror due to thermal shock, you may not be getting any benefit from the
steamer.

Scott Beard

________________________________
From: tsulmer1 <timulmer@...<mailto:timulmer%40tsu.ca>>
To: bigdob@yahoogroups.com<mailto:bigdob%40yahoogroups.com>
Sent: Sun, June 26, 2011 9:43:52 PM
Subject: [bigdob] Cleaning Telescope Mirror with Steam


I know the "usual" method for cleaning our mirrors: soap in warm water with a
couple drops of dove dish soap for 15 minutes, use a soft cotton cloth or cotton
balls and gentle clean (using no pressure and constantly moving to a clean
cotton ball or clean part of the cloth). Then rinse with distilled water and put
on its side to dry. I also blow it off with Aargon gas.

But for really caked on grime (pollens, etc.), you have to scrub and then come
the scratches.

So, I have an idea....Use the inexpensive steam cleaners you can buy at most
department stores. They blow hot steam under pressure to dislodge grime. People
use them to clean toilets, stoves, etc.

Anyone ever try this? Anything to be concerned about? I've put my hand in the
path of the steam and it is hot but not scalding until you get very very close
to the nozzle. My idea is to start further away and let the lower temp and
pressure work on the grime and slowly move closer (i.e. hot and more pressure)
for really stubborn grime.

But before I give it a go, I thought I canvas the collective experience of the
group. (I'm a little concerned about the coatings if I get to much heat and
pressure.)

Anyone?

Thanks, Tim in Calgary

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





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

#19991 From: William Blakeslee <williebluestar@...>
Date: Thu Jul 7, 2011 11:23 pm
Subject: CORRECTION: War dogs--Dogs that are US NAVY SEALS -- fantastic photos
williebluestar
Send Email Send Email
 
Some how the address got changed
Subject: Re: Fw: War dogs--Dogs that are US NAVY SEALS -- fantastic photos
 
http://blogs.canoe.ca/parker/general/the-dog-that-cornered-osama-bin-laden/
this says page not found....

-
War dogs--Dogs that are US NAVY SEALS -- fantastic photos
>
>More on the war dogs and links to the original ones that many have seen.  All
wonderful!
>War dogs--Dogs that are US NAVY SEALS
>>
>>Now you will know the rest of the story:
>>>http://blogs.canoe.ca/parker/general/the-dog-that-cornered-osama-bin-laden/  

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

#19992 From: "Mike Paulus" <mikepaulus79@...>
Date: Fri Sep 2, 2011 2:25 pm
Subject: Large fast dob
mikepaulus79
Send Email Send Email
 
Well this forum has been very quiet so I may as well try to liven it up.
I live in the Southern hemisphere and have ordered a 40 inch F3 from a well
respected US optician. My first view of the heavens apart from a crappy Kmart
scope many many years ago was through a 32 inch F3.6 Kennedy mirror and I must
say I was blown away. I knew then that I was lucky enough to have the funds to
afford that kind of a scope or better so I thought, why not? Rather than a new
Landcruiser or some other bauble, why not get something that totally grounds me
every time I use it? Just as important, I thought this type of scope would
possibly connect me with other people who had similar views to myself in terms
of our place in the universe and where we in the West are currently heading. I
hope for your best wishes as I embark upon my journey. For those of you in North
America, Europe and Australia who have never seen the full glory of the Southern
Sky in a big scope, I hope to be able to share my good fortune with you in the
not too distant future.

#19993 From: Attilla Danko <attilladanko@...>
Date: Fri Sep 2, 2011 2:45 pm
Subject: Re: Large fast dob
attilladanko
Send Email Send Email
 
I hope you have a very large guest room. :)

-ad

On Fri, Sep 2, 2011 at 10:25, Mike Paulus <mikepaulus79@...> wrote:

> **
>
>
> Well this forum has been very quiet so I may as well try to liven it up.
> I live in the Southern hemisphere and have ordered a 40 inch F3 from a well
> respected US optician. My first view of the heavens apart from a crappy
> Kmart scope many many years ago was through a 32 inch F3.6 Kennedy mirror
> and I must say I was blown away. I knew then that I was lucky enough to have
> the funds to afford that kind of a scope or better so I thought, why not?
> Rather than a new Landcruiser or some other bauble, why not get something
> that totally grounds me every time I use it? Just as important, I thought
> this type of scope would possibly connect me with other people who had
> similar views to myself in terms of our place in the universe and where we
> in the West are currently heading. I hope for your best wishes as I embark
> upon my journey. For those of you in North America, Europe and Australia who
> have never seen the full glory of the Southern Sky in a big scope, I hope to
> be able to share my good fortune with you in the not too distant future.
>
>
>



--
attilla danko, danko@..., http://cleardarksky.com/csk


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

#19994 From: "gumbydad2002" <wsrs@...>
Date: Mon Sep 5, 2011 12:58 pm
Subject: Re: Large fast dob
gumbydad2002
Send Email Send Email
 
Mike,
Who are you having make the primary and secondary mirrors? Who is going to make
the structure to carry these behemoth pieces of glass? Curious minds would like
to know<g>. BTW, congrats on stepping up to such large aperture. I can only
imagine how your Southern constellations are going to look in that beautiful
scope. We never have Omega Centauri more than about 10-15 degrees above the
horizon and you will be looking at it overhead with 40" of aperture! Bob

--- In bigdob@yahoogroups.com, "Mike Paulus" <mikepaulus79@...> wrote:
>
> Well this forum has been very quiet so I may as well try to liven it up.
> I live in the Southern hemisphere and have ordered a 40 inch F3 from a well
respected US optician. My first view of the heavens apart from a crappy Kmart
scope many many years ago was through a 32 inch F3.6 Kennedy mirror and I must
say I was blown away. I knew then that I was lucky enough to have the funds to
afford that kind of a scope or better so I thought, why not? Rather than a new
Landcruiser or some other bauble, why not get something that totally grounds me
every time I use it? Just as important, I thought this type of scope would
possibly connect me with other people who had similar views to myself in terms
of our place in the universe and where we in the West are currently heading. I
hope for your best wishes as I embark upon my journey. For those of you in North
America, Europe and Australia who have never seen the full glory of the Southern
Sky in a big scope, I hope to be able to share my good fortune with you in the
not too distant future.
>

#19995 From: "Shneor" <szsherm@...>
Date: Mon Sep 5, 2011 10:22 pm
Subject: Re: Large fast dob
szsherm
Send Email Send Email
 
Hi Mike,
I've been fortunate in having the use of a 24" at Magellan Observatory in
Australia for 8 nights (4 usable) a few years ago; in my opinion, the southern
skies are better than ours in terms of objects - we have nothing that can
compare to Eta Carinae or the Magellanics, for example. Before that, in 2000, I
took a 13.1" with me to South Island, New Zealand (45° south latitude) for a
couple of weeks. Having a 1-meter telescope there will be terrific!. Where are
you located? When do you expect delivery?
Clears,
Shneor

--- In bigdob@yahoogroups.com, "Mike Paulus" <mikepaulus79@...> wrote:
>
> Well this forum has been very quiet so I may as well try to liven it up.
> I live in the Southern hemisphere and have ordered a 40 inch F3 from a well
respected US optician. My first view of the heavens apart from a crappy Kmart
scope many many years ago was through a 32 inch F3.6 Kennedy mirror and I must
say I was blown away. I knew then that I was lucky enough to have the funds to
afford that kind of a scope or better so I thought, why not? Rather than a new
Landcruiser or some other bauble, why not get something that totally grounds me
every time I use it? Just as important, I thought this type of scope would
possibly connect me with other people who had similar views to myself in terms
of our place in the universe and where we in the West are currently heading. I
hope for your best wishes as I embark upon my journey. For those of you in North
America, Europe and Australia who have never seen the full glory of the Southern
Sky in a big scope, I hope to be able to share my good fortune with you in the
not too distant future.
>

#19996 From: "gumbydad2002" <wsrs@...>
Date: Mon Sep 5, 2011 11:12 pm
Subject: Re: Large fast dob
gumbydad2002
Send Email Send Email
 
Mike,
I noticed on a recent post by Mike Lockwood that he is currently working on a
1.1 meter mirror. That sounds surprisingly close to what you are getting<g>. If
in fact you are getting one of Lockwood's mirrors, you will be in for a treat. I
have a 28" f/3.54 Lockwood/Starmaster and really love how the scope/mirror
performs. Of course we only have steady Florida skies and cannot go lower that
18 degrees latitude down in the Keys. We get a little glimpse of what you have
overhead. The only thing is that the Moon is corretly positioned here and upside
down for you guys<g>. Bob

--- In bigdob@yahoogroups.com, "gumbydad2002" <wsrs@...> wrote:
>
> Mike,
> Who are you having make the primary and secondary mirrors? Who is going to
make the structure to carry these behemoth pieces of glass? Curious minds would
like to know<g>. BTW, congrats on stepping up to such large aperture. I can only
imagine how your Southern constellations are going to look in that beautiful
scope. We never have Omega Centauri more than about 10-15 degrees above the
horizon and you will be looking at it overhead with 40" of aperture! Bob
>
> --- In bigdob@yahoogroups.com, "Mike Paulus" <mikepaulus79@> wrote:
> >
> > Well this forum has been very quiet so I may as well try to liven it up.
> > I live in the Southern hemisphere and have ordered a 40 inch F3 from a well
respected US optician. My first view of the heavens apart from a crappy Kmart
scope many many years ago was through a 32 inch F3.6 Kennedy mirror and I must
say I was blown away. I knew then that I was lucky enough to have the funds to
afford that kind of a scope or better so I thought, why not? Rather than a new
Landcruiser or some other bauble, why not get something that totally grounds me
every time I use it? Just as important, I thought this type of scope would
possibly connect me with other people who had similar views to myself in terms
of our place in the universe and where we in the West are currently heading. I
hope for your best wishes as I embark upon my journey. For those of you in North
America, Europe and Australia who have never seen the full glory of the Southern
Sky in a big scope, I hope to be able to share my good fortune with you in the
not too distant future.
> >
>

#19997 From: John Mahony <jmmahony@...>
Date: Tue Sep 6, 2011 12:27 am
Subject: Re: Re: Large fast dob
jmmahony
Send Email Send Email
 
----- Original Message -----

> From: gumbydad2002 <wsrs@...>
>
> Mike,
> I noticed on a recent post by Mike Lockwood that he is currently working on a
> 1.1 meter mirror. That sounds surprisingly close to what you are
> getting<g>.

But that might be the 1.1m cellular mirror first mentioned here a few years ago-
I'm pretty sure he's doing that one (after very long delays in finding someone
who could make the cellular blank).

OTOH, who else is known for making such large, fast mirrors?

-John


> If in fact you are getting one of Lockwood's mirrors, you
> will be in for a treat. I have a 28" f/3.54 Lockwood/Starmaster and really
> love how the scope/mirror performs. Of course we only have steady Florida
skies
> and cannot go lower that 18 degrees latitude down in the Keys. We get a little
> glimpse of what you have overhead. The only thing is that the Moon is corretly
> positioned here and upside down for you guys<g>. Bob
>
> --- In bigdob@yahoogroups.com, "gumbydad2002" <wsrs@...> wrote:
>>
>>  Mike,
>>  Who are you having make the primary and secondary mirrors? Who is going to
> make the structure to carry these behemoth pieces of glass? Curious minds
would
> like to know<g>. BTW, congrats on stepping up to such large aperture. I
> can only imagine how your Southern constellations are going to look in that
> beautiful scope. We never have Omega Centauri more than about 10-15 degrees
> above the horizon and you will be looking at it overhead with 40" of
> aperture! Bob
>>
>>  --- In bigdob@yahoogroups.com, "Mike Paulus"
> <mikepaulus79@> wrote:
>>  >
>>  > Well this forum has been very quiet so I may as well try to liven it
> up.
>>  > I live in the Southern hemisphere and have ordered a 40 inch F3 from a
> well respected US optician. My first view of the heavens apart from a crappy
> Kmart scope many many years ago was through a 32 inch F3.6 Kennedy mirror and
I
> must say I was blown away. I knew then that I was lucky enough to have the
funds
> to afford that kind of a scope or better so I thought, why not? Rather than a
> new Landcruiser or some other bauble, why not get something that totally
grounds
> me every time I use it? Just as important, I thought this type of scope would
> possibly connect me with other people who had similar views to myself in terms
> of our place in the universe and where we in the West are currently heading. I
> hope for your best wishes as I embark upon my journey. For those of you in
North
> America, Europe and Australia who have never seen the full glory of the
Southern
> Sky in a big scope, I hope to be able to share my good fortune with you in the
> not too distant future.
>>  >
>>
>
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>

#19998 From: "parabola30" <parabola30@...>
Date: Tue Sep 6, 2011 1:25 am
Subject: Re: Large fast dob
parabola30
Send Email Send Email
 
Hi,

--- In bigdob@yahoogroups.com, John Mahony <jmmahony@...> wrote:
> > From: gumbydad2002 <wsrs@...>
> > I noticed on a recent post by Mike Lockwood that he is currently
> > working on a
> > 1.1 meter mirror. That sounds surprisingly close to what you are
> > getting<g>.

> But that might be the 1.1m cellular mirror first mentioned here a
> few years ago- I'm pretty sure he's doing that one (after very
> long delays in finding someone who could make the cellular blank).

You're close - it's a 1.1m monolithic Supremax replacement for a cellular blank
that never showed up.  One vendor never delivered, and another declined to
produce it.

I am producing two 40" f/3s for clients (one amateur, one scientific), and one
for myself if I ever get time to finish it!  There are a number of other 40"+
mirrors in the queue too.

I recently completed a 50" f/2.2 R-C primary, and will be testing it in
combination with a secondary mirror soon, in order to verify the figure of the
secondary mirror.

> OTOH, who else is known for making such large, fast mirrors?

Some claim to.  Do your research and be careful who you give your money to.

Mike Lockwood

#19999 From: "Alvin Huey" <alvin@...>
Date: Tue Sep 6, 2011 2:27 am
Subject: re: Re: Large fast dob
generalragesc
Send Email Send Email
 
> OTOH, who else is known for making such large, fast mirrors?


Some claim to.  Do your research and be careful who you give your money to.


Steve Kennedy also makes excellent fast mirrors and have been making them longer
than anyone else.  I have not seen a bad Kennedy mirror and I have looked
through at least ten of them including recent examples.  I don't know what
happened with Wambo's mirror, but given how that process and review evolved, I
have serious doubts about the validity of the review.    Steve never had a
chance to look at the mirror so we will never know what happened.


Also for all of you to know, Kennedy is now using OMI as his coater as he had
some serious problems with Flabeg...Wambo's mirror included.


BTW, Kennedy will be making my next fast 28" mirror.


Clear skies,

Alvin






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

#20000 From: "daveleason" <davensldvd@...>
Date: Wed Sep 7, 2011 8:38 am
Subject: Re: Large fast dob
daveleason
Send Email Send Email
 
"Steve Kennedy also makes excellent fast mirrors and have been making them
longer than anyone else.  I have not seen a bad Kennedy mirror and I have looked
through at least ten of them including recent examples..."
Alvin

Respectfully, it's a good thing you never observed with my K32.  Your "have not
seen" record would have quickly come to an end.

Good Luck with your next Kennedy mirror.

dave

#20001 From: "Alvin Huey" <alvin@...>
Date: Wed Sep 7, 2011 3:26 pm
Subject: re: Re: Large fast dob
generalragesc
Send Email Send Email
 
Hi Dave,


I know of two "bad" 32 inch mirrors. Do you have the other Webster 32?  Did you
talk with Kennedy to resolve the issue?  I know of two others had their mirrors
recoated at OMI and one of them got it back and the difference was night and
day.  The figure was fine, just the coating.  The other didn't get it back yet
as it is being coated now.  One is a 30" f/3.3 and other is 24" f/3.3.


I think your issue might be just the coating.  Talk with Kennedy if you haven't
yet.


Best,

Alvin

----------------------------------------

From: "daveleason" <davensldvd@...>

Sent: Wednesday, September 07, 2011 1:39 AM

To: bigdob@yahoogroups.com

Subject: [bigdob] Re: Large fast dob




"Steve Kennedy also makes excellent fast mirrors and have been making them
longer than anyone else.  I have not seen a bad Kennedy mirror and I have looked
through at least ten of them including recent examples..."

Alvin


Respectfully, it's a good thing you never observed with my K32.  Your "have not
seen" record would have quickly come to an end.


Good Luck with your next Kennedy mirror.


dave






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

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