Hi all. I'll be doing some travel in Italy this summer -- for the month of July.

If anyone is around who lives there-abouts, I'd love to meet a fellow
astronomer/telescope maker. Let me know. My email is densteele@...

thanks, Dennis

Big dobsonian telescope users.Hi Dennis,
I live in Italy, near Mantova. Let me know if Mantova is near your route.
Fabio
   ----- Original Message -----
   From: bigdob@yahoogroups.com
   To: bigdob@yahoogroups.com
   Sent: Monday, May 02, 2011 9:31 AM
   Subject: [bigdob] Digest Number 3098


   Big dobsonian telescope users.
   Messages In This Digest (1 Message)
     1. Travel in Italy this summer From: Dennis
   View All Topics | Create New Topic Message
     1. Travel in Italy this summer
     Posted by: "Dennis" densteele@...   densteele
     Sun May 1, 2011 1:59 pm (PDT)


     Hi all. I'll be doing some travel in Italy this summer -- for the month of
July.

     If anyone is around who lives there-abouts, I'd love to meet a fellow
astronomer/telescope maker. Let me know. My email is densteele@...

     thanks, Dennis


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

I am dyslexic. I have observed the majority of the NGC catalogue, but can not
tell you the M number of a single Messier. I am quite proficient at star
hopping.

David Pitre

--- In bigdob@yahoogroups.com, "Dick" <rmcarner@...> wrote:
>
>
>
>
> --- In bigdob@yahoogroups.com, "Fabio" <cielobuio@> wrote:
> >
> > Dear Dick,
> > I once read that dislexia is more frequent in people talking languages (such
as English) that haven't a biunivocal relation between the written and its
pronunciation. A biunivocal relation exist, for example, in German and Italian.
>
> Interesting theory. However, currently the preponderance of research suggests
that dyslexia is a neurological condition. To be describe it in simple terms:
The brains of dyslexic people are wired differently. Genes associated with this
condition have been tentatively identified. There is evidence that dyslexia
'runs' in families. On the upside, people with dyslexia excel in what is called
lateral thinking. That implies that they will be very proficient at star hopping
using star charts. :-)
> > About AO again, it will also correct, when corecting for the rest, slight
miscollimations.
>
> Okay. Can't wait..
> Dick
>

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 motorcycle
fairing designs, but lots of other cool stuff.  Be sure you check out his
website.
http://www.craigvetter.com/pages/Motorcycle_Designs/defiant.html

and at 125 mils per gallon his motorcycle =
http://www.craigvetter.com/pages/Motorcycle_Designs/Streamliner.html

Hope you like them!
Dave_D


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

Hello,

This email message is a notification to let you know that
a file has been uploaded to the Files area of the bigdob
group.

   File        : /Collimation article version 4.pdf
   Uploaded by : pensack1 <Pensack1@...>
   Description : Newtonian Collimation version 4

You can access this file at the URL:
http://groups.yahoo.com/group/bigdob/files/Collimation%20article%20version%204.p\
df

To learn more about file sharing for your group, please visit:
http://help.yahoo.com/l/us/yahoo/groups/original/members/web/index.html
Regards,

pensack1 <Pensack1@...>

People,
I have just uploaded to the files the latest version (v.4) of my article on
collimation of newtonians.
Please feel free to email me any comments or criticisms.
I hope this helps.

Don Pensack
Los Angeles

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]
>

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]

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 .
:)

----- 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

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
>
>
>
>

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]

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.

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]

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]
>

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
>

--- 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
> >
>

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

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
>
>
>

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.

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]

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
> >
> >
> >
>

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]

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]
>
>

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]

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]

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.

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]

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.
>

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.
>