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Re: [ATM] Dobson film "review"



 Just some thoughts on the Dobson "film review". I think it's important to seperate ones view point of an individual from the body of work ( in this case a film) that addresses that persons life. 
   "A Sidewalk Astronomer" , in my view point , hit the nail on the head so to speak in profiling the character that is John Dobson. To summarize the film with a weakness of John's is to do a disservice to the film itself, and in fact , to John. His contributions to astronomy and his approach to both astronomy and cosmology shine through in the film and far outweigh the ego of Johns that does reveal itself from time to time.
    The film does cover quite a bit of ground benefical to the lay-person,  not only in the astronomical realm,but of course, Johns life . It is, after all , a biographical documentary, replete with Johns strengths and weaknesses, although I have to say in Johns defense, his ire isn't raised (in one scene)because some one questions his cosmological idealogy, it's because he 's mis-interpreted and mis-quoted. When the film "Universe-Cosmology Quest" was first premiered down in L.A. two years ago, John was the first one to broach the issue of the film not adequately covering the Big -Bangers point of view.
    As far as this being a technical film for telescope makers, it is definitely not. As for the Big Bang itself, how do you get something from nothing????;)


    Jeff Newsom









-----Original Message-----
From: atm-request@atmlist.net
Sent: Sep 26, 2005 9:00 PM
To: atm@atmlist.net
Subject: ATM Digest, Vol 21, Issue 32

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Today's Topics:

   1. Re: beveling edge (Kevin MIchael Zabbo)
   2. Stepper Stuff (Kevin MIchael Zabbo)
   3. Re: Stepper Stuff (Nils Olof Carlin)
   4. Re: Focuser, Derotator, Off Axis Guider (Andy Saulietis)
   5. Re: Mirror clips (Mike Lockwood)
   6. Re: Stepper Stuff (matt)
   7. Re: Amateur Telescope Makers Books (Ellen Mackenzie)
   8. Re: Mirror clips (Bob May)
   9. too thin tube? (Ukyo Chen)
  10. Re: too thin tube? (Richard)
  11. Re: too thin tube (Ellen Mackenzie)
  12. GSUM hypothesis (Richard F.L.R. Snashall)
  13. Re: Mirror clips (Jason Hissong)
  14. Re: Mirror clips (Jerry)
  15. Re: Mirror clips (Jason Hissong)
  16. Fwd: Re:  Mirror clips (Ken Hunter)


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

Message: 1
Date: Sun, 25 Sep 2005 21:34:43 -0700 (PDT)
From: Kevin MIchael Zabbo <chaosopher23@yahoo.com>
Subject: Re: [ATM] beveling edge
To: Peter Abrahams <telscope@europa.com>, atm@atmlist.net
Message-ID: <20050926043443.60652.qmail@web33010.mail.mud.yahoo.com>
Content-Type: text/plain; charset=iso-8859-1

If you have a power sander that can be worked wet,
load a piece of #60 or coarser auto-body sander into
it and use that.  It's easier and not as slow as the
whetstone.

I know, you may think I'm crazy, but this will work if
you're not too forceful.  I had my edge beveled with a
large wet band sander at a glassworking place.  It
took all of a couple of minutes to put a good 45 on
the edge.

Kevin of Eastern Iowa
Seeker of the Darkness

--- Peter Abrahams <telscope@europa.com> wrote:

> > What is the best way to bevel the edge of glass
> disks?
> > I've used a whet stone by hand but this becomes
> very
> > tiring.  TIA,
> 
> Diamond grit files, available in 220 or 320 grit,
> should be cheap in small sizes 
> (under $5. for a small one, like 15mm x 75mm), and
> cut glass very quickly.  Use 
> with lots of water to prolong grit life (the diamond
> takes years to wear out but 
> will get knocked off the file with hard dry use).
> Get them at lapidary stores, gun shows, or some
> hardware stores.
> --Peter
> _______________________________________________
> ATM mailing list http://www.atmlist.net/
> 


I published my first novel!  You can get it here, from the publisher!  
http://www.publishamerica.com/

Their search stringbox is on the right side about halfway down.

search using my name:  kevin michael zabbo
and it will take you right to my book page.

The title is anna's blood, which also takes you there.

Please order your copy soon!  I love you!


		
__________________________________ 
Yahoo! Mail - PC Magazine Editors' Choice 2005 
http://mail.yahoo.com


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

Message: 2
Date: Sun, 25 Sep 2005 21:41:41 -0700 (PDT)
From: Kevin MIchael Zabbo <chaosopher23@yahoo.com>
Subject: [ATM] Stepper Stuff
To: atm@atmlist.net
Message-ID: <20050926044141.51213.qmail@web33006.mail.mud.yahoo.com>
Content-Type: text/plain; charset=iso-8859-1

The steppers I have are from old disk drives.  I have
a couple from the old TEAC 1/2 height 5.25's that have
some decent torque and work in 3.6 degree steps. 
That's 100 steps per revolution...  ok, that part's
easy.

I'm going to run the motor on a 8" f/6 Newt and
another on a 13.25" f/20-something Cass-variation. 
Equatorial, maximum magnification and stability is
desired, probably both forks with conical
right-ascension axles.

What's a good reduction for these motors so that they
don't go too fast when doing one step at a time?

Kevin of Eastern Iowa
Seeker of the Darkness

I published my first novel!  You can get it here, from the publisher!  
http://www.publishamerica.com/

Their search stringbox is on the right side about halfway down.

search using my name:  kevin michael zabbo
and it will take you right to my book page.

The title is anna's blood, which also takes you there.

Please order your copy soon!  I love you!


		
__________________________________ 
Yahoo! Mail - PC Magazine Editors' Choice 2005 
http://mail.yahoo.com


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

Message: 3
Date: Mon, 26 Sep 2005 16:42:25 +0200 (MEST)
From: Nils Olof Carlin <nilsolof.carlin@telia.com>
Subject: Re: [ATM] Stepper Stuff
To: chaosopher23@yahoo.com, atm@atmlist.net
Message-ID: <6197636.1127745745777.JavaMail.tomcat@pne-ps2-sn2>
Content-Type: text/plain;charset="ISO-8859-1"

Kevin,


>>>
The steppers I have are from old disk drives.  I have
a couple from the old TEAC 1/2 height 5.25's that have
some decent torque and work in 3.6 degree steps. 
That's 100 steps per revolution...  ok, that part's
easy.

I'm going to run the motor on a 8" f/6 Newt and
another on a 13.25" f/20-something Cass-variation. 
Equatorial, maximum magnification and stability is
desired, probably both forks with conical
right-ascension axles.

What's a good reduction for these motors so that they
don't go too fast when doing one step at a time?>>>

I would suggest that you aim for 25-30 fullsteps or halfsteps per 
second (the apparent motion of an object near the celestial equator is 
15 arcsec per second of time - 30 steps/sec is 1/2 arcsec per step) - 
there will be some inertia to smooth out the motion but there may be 
resonances in the telescope - perhaps in the secondary and spider, that 
can amplify vibrations.

This means 1 turn per 3-4 sec or so - 15-20 turns per minute or 900-
1200 per hour or 21600-28800 turns per 24 hr for fullstep (half that 
for halfstep), if I didn't miscalculate - this gives the total gear 
reduction to aim for. At least, don't go much below.

Nils Olof


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

Message: 4
Date: Mon, 26 Sep 2005 08:52:47 -0600
From: Andy Saulietis <iss@pvtnetworks.net>
Subject: Re: [ATM] Focuser, Derotator, Off Axis Guider
To: martin.cibulski@t-online.de
Cc: atm@atmlist.net
Message-ID: <6.2.3.4.1.20050926085047.01c4eea0@pvtnetworks.net>
Content-Type: text/plain; charset="us-ascii"; format=flowed

Hello Martin,



Chuck Shaw and I built several variants of field de-rotated guidescopes,
they work but are mechanically complex.

http://www.ghg.net/cshaw/guiderot.htm

Here's info on Chuck Shaw's site on derotated guidescopes..his
ISP was off line because of Rita the last few days.

Andy
Andy Saulietis
ISS Enterprises
10 Milky Way
Mayhill NM 88339


World's first astronomy land development:

http://www.pvtnetworks.net/~iss/starend1.htm

15 of 17 lots sold to astronomers as of 2/08/05

505-687-3067 voice/fax, call voice or e-mail to set up
e-mail: iss@pvtnetworks.net

Also available: Custom large telescopes/mounts,
25 & 50 mm manual filter wheels, HDPE worm gears & clutches,
HDPE friction drives, CCD sliders & turrets, custom
telescope parts machining.





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

Message: 5
Date: Mon, 26 Sep 2005 10:16:07 -0500
From: Mike Lockwood <melockwo@uiuc.edu>
Subject: Re: [ATM] Mirror clips
To: atm@atmlist.net
Message-ID: <433810B7.5000103@uiuc.edu>
Content-Type: text/plain; charset=us-ascii; format=flowed

Jason,

How is the figuring going?

Jason Hissong wrote:
> Drawing out the plans for my 8" sphere-o-scope and I went to Home Depot 
> today to scope out materials.  I am pretty much finding what I need... 
> except something for mirror clips.  I found angle brackets, but none of 
> them have an elongated slot like I see in so many mirror clips around.  
> Is that just something you make with a drill and a file?

I swear - only serious answers here....

I try not to have ANY metal touching my optics.

I like to use small pieces of non-brittle plastic for the clips, and I 
  angle the underside so that they have the same angle as the bevel of 
the mirror.  Therefore, they only contact the mirror on the bevel, not 
on the optical surface, and I don't get marks on the coating from the 
mirror rattling against the clips.  I extend the clips 1/16-1/8" over 
the optical surface, and secure with a bolt/screw.

The overall shape of the clip ends up like:

  ---------------
|              |
|             /
|            /
|           /
  -----------

The best type of plastic for this is a type that is slightly soft, but 
is still hard enough to drill and tap.  It is not brittle type that 
will crack under pressure.  I got some white plastic at a plastic 
supply place that is a little softer than PVC.  Might be Nylon. 
Teflon would probably work, too.  Typical clip dimensions are 1/2" 
wide by 1" long by 1/2" tall, again with only a little extending over 
the mirror.  The plastic can be cut with a hacksaw or fine-toothed 
hand saw.  A sharp knife cleans up the corners/surfaces.

For you, an 8" mirror is light and the structural requirements for the 
clips will be minimal.

By the way, typically all the support points in my cells are small 
teflon pads.  That is only one way to do it, but it works for me.

	Mike Lockwood



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

Message: 6
Date: Mon, 26 Sep 2005 11:47:22 -0400
From: "matt" <electro_optic@bellsouth.net>
Subject: Re: [ATM] Stepper Stuff
To: "Nils Olof Carlin" <nilsolof.carlin@telia.com>,
	<chaosopher23@yahoo.com>,	<atm@atmlist.net>
Message-ID: <001a01c5c2b1$962da1a0$b4fea8c0@sat1800>
Content-Type: text/plain;	charset="iso-8859-1"

from my old days of designing stepper based disk drives , printers and
plotters for my day job as electronics design engineer , steppers of that
size and type have a start stop frequency in the hundreds of steps/second .
That meaning the rotor has time to come to a full stop between steps that
are lower frequency than the start stop.
The stepper gets into the slewing region only above the start/stop
frequency, and that is the only area of operation where there is any
smoothing out of steps due to inertia .
For step frequencies under the start stop frequency , there are actually
some frequency values where there is considerable rotor position overshoot
quite the opposite of smoothing out . Running under the start stop frequency
is the roughest area of operation on the torque vs. frequency stepper curve
. Use at least some microstepping to smooth out the vibrations or some other
means , like air dashpots, inertial disk dampers on the rotor , and plenty
of friction in the drive train. A common mistake is trying to eliminate
friction, which leads to an underdamped system with high overshoot .

best regards,
matt tudor

-----Original Message-----
From: Nils Olof Carlin <nilsolof.carlin@telia.com>
To: chaosopher23@yahoo.com <chaosopher23@yahoo.com>; atm@atmlist.net
<atm@atmlist.net>
Date: Monday, September 26, 2005 10:46 AM
Subject: Re: [ATM] Stepper Stuff


>Kevin,
>
>
>>>>
>The steppers I have are from old disk drives.  I have
>a couple from the old TEAC 1/2 height 5.25's that have
>some decent torque and work in 3.6 degree steps.
>That's 100 steps per revolution...  ok, that part's
>easy.
>
>I'm going to run the motor on a 8" f/6 Newt and
>another on a 13.25" f/20-something Cass-variation.
>Equatorial, maximum magnification and stability is
>desired, probably both forks with conical
>right-ascension axles.
>
>What's a good reduction for these motors so that they
>don't go too fast when doing one step at a time?>>>
>
>I would suggest that you aim for 25-30 fullsteps or halfsteps per
>second (the apparent motion of an object near the celestial equator is
>15 arcsec per second of time - 30 steps/sec is 1/2 arcsec per step) -
>there will be some inertia to smooth out the motion but there may be
>resonances in the telescope - perhaps in the secondary and spider, that
>can amplify vibrations.
>
>This means 1 turn per 3-4 sec or so - 15-20 turns per minute or 900-
>1200 per hour or 21600-28800 turns per 24 hr for fullstep (half that
>for halfstep), if I didn't miscalculate - this gives the total gear
>reduction to aim for. At least, don't go much below.
>
>Nils Olof
>_______________________________________________
>ATM mailing list http://www.atmlist.net/
>



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

Message: 7
Date: Tue, 27 Sep 2005 11:14:07 -0700
From: "Ellen Mackenzie" <mackenzieconsulting@sympatico.ca>
Subject: Re: [ATM] Amateur Telescope Makers Books
To: "ATM" <atm@atmlist.net>
Message-ID: <BAYC1-PASMTP02E60FA9A268851E829B5DD48B0@CEZ.ICE>
Content-Type: text/plain;	charset="us-ascii"

I am surprised when there was no rebuttal when Gary said there was no
three volumes of the ATM books published by Scientific American and edited
by Ingalls. These books are classics although they should be properly
named the Amateur Astronomers Hand books. A fourth book is definitely
needed to cover the advances made since the set's publication in 1963, but
the original set has so much information I feel it is a "must have" for
the beginning telescope maker. 



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

Message: 8
Date: Mon, 26 Sep 2005 09:19:14 -0700
From: "Bob May" <bobmay@nethere.com>
Subject: Re: [ATM] Mirror clips
To: <atm@atmlist.net>
Message-ID: <001801c5c2b6$09c26b60$1600a8c0@amd>
Content-Type: text/plain;	charset="iso-8859-1"

I probably should have said big tool rather than just tool.
Bob May
bobmay at nethere.com
http: slash /nav.to slash bobmay
http: slash /bobmay dot astronomy.net
Addresses have been munged up to keep spammers from bothering me.
replace the obvious words with the proper character.
Thank you for your understanding!



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

Message: 9
Date: Mon, 26 Sep 2005 10:11:53 -0700
From: "Ukyo Chen" <ukyochen888@hotmail.com>
Subject: [ATM] too thin tube?
To: <atm@atmlist.net>
Message-ID: <BAY0-DAV-04074FE324975C5A2CE9FA3FF8B0@phx.gbl>
Content-Type: text/plain;	charset="iso-8859-1"

Dear ATMers,
I got a 129mm duralumin (enhanced Al) tube, want to make screw thread inside it and put 127mm lenses in. The question is, if 1mm is too thin for a 127mm duralumin tube? Thanks for any suggestions!

Best Regards,
Ukyo Chen



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

Message: 10
Date: Mon, 26 Sep 2005 18:56:32 +0100
From: Richard <cnc@cncservo.co.uk>
Subject: Re: [ATM] too thin tube?
To: "Ukyo Chen" <atm@atmlist.net>
Cc: atm@atmlist.net
Message-ID: <134605219.20050926185632@cncservo.co.uk>
Content-Type: text/plain; charset=us-ascii

Hi Ukyo,

Monday, September 26, 2005, 6:11:53 PM, you wrote:

UC> I got a 129mm duralumin (enhanced Al) tube, want to make
UC> screw thread inside it and put 127mm lenses in. The question
UC> is, if 1mm is too thin for a 127mm duralumin tube?

The only way you will thread it is to screwcut it in a lathe and
I would think it is too flexible to easily hold it in a lathe.
You will also have to use a very fine thread to avoid weakening
the tube too much. It really needs to be at least twice the wall
thickness. 2.5mm or 3mm wall should be OK.

-- 

Best regards,
  Richard in the UK



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

Message: 11
Date: Tue, 27 Sep 2005 13:31:51 -0700
From: "Ellen Mackenzie" <mackenzieconsulting@sympatico.ca>
Subject: Re: [ATM] too thin tube
To: "ATM" <atm@atmlist.net>
Message-ID: <BAYC1-PASMTP0563AE3D21BDE82B2D4B77D48B0@CEZ.ICE>
Content-Type: text/plain;	charset="us-ascii"

Hi Ukyo:
	You didn't give the wall thickness of the tube. You can turn an
extra fine thread on the lathe or an incomplete internal thread to match
the thread on the lens barrel if you first make a sturdy collar to fit the
external diameter of the tube to prevent it from stretching out away from
the cutter. I am assuming this is what you want to do.
	I have many lens parts that are fully threaded and are only 1 mm
thick, this works out to around 0.4 mm per thread a little over 50 threads
to the inch.



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

Message: 12
Date: Mon, 26 Sep 2005 16:13:04 -0400
From: "Richard F.L.R. Snashall" <rflrs@rcn.com>
Subject: [ATM] GSUM hypothesis
To: ATM List <atm@atmlist.net>
Message-ID: <43385650.70108@rcn.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

In ATM 2, Gee gives the G-Sum equations for spherical aberration
and coma.  If one considers the restricted case where the crown,
with known refractive index, is first and the last surface is flat,
then the equation for spherical aberration, upon attempting to
find a solution, ends up being a quartic in the refractive index
of the flint element.  Similarly, the equation for coma ends up
being a cubic in the refractive index of the flint element.
I hypothesize that the solution to the equation for spherical
aberration is always higher than the crown refractive index.  Also,
the solution to the equation for coma is always lower than the crown
refractive index.  Equality of the two solutions only occurs when
the first surface is flat -- it ends up with zero power.

But... I haven't been able to prove it.  All I have is empirical
evidence.


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

Message: 13
Date: Mon, 26 Sep 2005 21:52:54 -0400
From: Jason Hissong <jhissong@gmail.com>
Subject: Re: [ATM] Mirror clips
To: atm@atmlist.net
Message-ID: <4338A5F6.3010900@gmail.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

Hi Mike,

Well, I started figuring, but I am having trouble keeping things secure 
on my turntable when I am at a large overhang, so I got some zones 
starting to happen.  The surface is getting a little rough from things 
not being very secure.  However, after the first session of figuring the 
slight oblate sphere became more spherical.. i.e., the center finally 
started to deepen so that it was meeting up with the raised zone.  It is 
neat to actually see things change like they are.  I think I solved my 
turntable problem... however, there is still a turn down edge that I may 
work on.  Going back to some polishing strokes to resolved that.. I 
could also just mask it as my mirror is really an 8.125" mirror and it 
looks like just the outer 1/8 is turned down?

http://www.undermidnight.com/images/atm/sphere_3.jpg
http://www.undermidnight.com/images/atm/sphere_3_oroc.jpg

As far as the mirror clips go... thanks for the tips (that goes for 
everyone!! chuckle)  I will try to keep the material coming... lol

I was going to use felt or cork for the surface that would touch the 
mirror, but I like your idea Mike.

As an aside, I want to thank folks like you, Bob, etc. who have provided 
some great material on the web for beginners like me.  I have your 
typical telescope making books.. but Mike, your explanation on figuring 
made the light to go on and I think I have a very good idea on how the 
various strokes work.  I will probably stick to Ronchi diagrams as it 
seems to be easier for me.. I am having a hard time with the couder mask 
interpreting when I have a particular zone nulled.  It seems that 
matching ronchi pattens are only slightly more subjective than a 
foucault test (at least for me) and easier .  The matching ronchi 
diagrams for my mirror are exact (in terms of a spherical surface).  The 
amount of lines and everything look like the diagrams except for the 
turned edge.

Also, I got my 13 year old brother interested... he is now working on a 
6" mirror.  So we are building scopes together.

Thanks again guys.. I will post my progress..

Jason Hissong



Mike Lockwood wrote:

> Jason,
>
> How is the figuring going?
>
>  
>
> I swear - only serious answers here....
>
> I try not to have ANY metal touching my optics.
>
> I like to use small pieces of non-brittle plastic for the clips, and I 
>  angle the underside so that they have the same angle as the bevel of 
> the mirror.  Therefore, they only contact the mirror on the bevel, not 
> on the optical surface, and I don't get marks on the coating from the 
> mirror rattling against the clips.  I extend the clips 1/16-1/8" over 
> the optical surface, and secure with a bolt/screw.
>
> The overall shape of the clip ends up like:
>
>  ---------------
> |              |
> |             /
> |            /
> |           /
>  -----------
>
> The best type of plastic for this is a type that is slightly soft, but 
> is still hard enough to drill and tap.  It is not brittle type that 
> will crack under pressure.  I got some white plastic at a plastic 
> supply place that is a little softer than PVC.  Might be Nylon. Teflon 
> would probably work, too.  Typical clip dimensions are 1/2" wide by 1" 
> long by 1/2" tall, again with only a little extending over the 
> mirror.  The plastic can be cut with a hacksaw or fine-toothed hand 
> saw.  A sharp knife cleans up the corners/surfaces.
>
> For you, an 8" mirror is light and the structural requirements for the 
> clips will be minimal.
>
> By the way, typically all the support points in my cells are small 
> teflon pads.  That is only one way to do it, but it works for me.
>
>     Mike Lockwood
>
> _______________________________________________
> ATM mailing list http://www.atmlist.net/
>
>  
>



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

Message: 14
Date: Mon, 26 Sep 2005 22:37:48 -0400
From: "Jerry" <wa4guu@verizon.net>
Subject: Re: [ATM] Mirror clips
To: "'Jason Hissong'" <jhissong@gmail.com>,	<atm@atmlist.net>
Message-ID: <001301c5c30c$77ec83e0$0100a8c0@D85SJB21>
Content-Type: text/plain; charset=us-ascii

Hello Jason:

Your Ronchigrams have some strange characteristics.

Particularly the outside image the dark lines narrow at the ends but do not
change spacing center to center much. The light areas should bend in the
same way as the dark.

On the inside image at the bottom the same effect is seen in reverse. Not so
evident at the top. 

Are the lines on your grating straight and of constant width? How long is
your slit?

I am having a hard time visualizing a mechanism for the effect.

 

Jerry




-----Original Message-----
From: atm-bounces@atmlist.net [mailto:atm-bounces@atmlist.net] On Behalf Of
Jason Hissong


http://www.undermidnight.com/images/atm/sphere_3.jpg
http://www.undermidnight.com/images/atm/sphere_3_oroc.jpg






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

Message: 15
Date: Mon, 26 Sep 2005 22:51:07 -0400
From: Jason Hissong <jhissong@gmail.com>
Subject: Re: [ATM] Mirror clips
To: Jerry <wa4guu@verizon.net>
Cc: atm@atmlist.net
Message-ID: <4338B39B.4040304@gmail.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

Hi Jerry,

I think the artifacts are because of the camera lense and me not holding 
the camera exactly straight.  It seems to do it more outside ROC.  
However, when I look with my eye, those effects are not seen.  It does 
make you scratch your head doesn't it? :)

Jason

Jerry wrote:

>Hello Jason:
>
>Your Ronchigrams have some strange characteristics.
>
>Particularly the outside image the dark lines narrow at the ends but do not
>change spacing center to center much. The light areas should bend in the
>same way as the dark.
>
>On the inside image at the bottom the same effect is seen in reverse. Not so
>evident at the top. 
>
>Are the lines on your grating straight and of constant width? How long is
>your slit?
>
>I am having a hard time visualizing a mechanism for the effect.
>
> 
>
>Jerry
>
>
>
>
>-----Original Message-----
>From: atm-bounces@atmlist.net [mailto:atm-bounces@atmlist.net] On Behalf Of
>Jason Hissong
>
>
>http://www.undermidnight.com/images/atm/sphere_3.jpg
>http://www.undermidnight.com/images/atm/sphere_3_oroc.jpg
>
>
>
>
>
>  
>



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

Message: 16
Date: Mon, 26 Sep 2005 19:58:18 -0700 (PDT)
From: Ken Hunter <atm_ken_hunter@yahoo.com>
Subject: [ATM] Fwd: Re:  Mirror clips
To: atm@atmlist.net
Message-ID: <20050927025818.8279.qmail@web52706.mail.yahoo.com>
Content-Type: text/plain; charset=iso-8859-1



Jason...
 
Re: masking a TDE.
 
Do you want to save an hour or two now just to live with a less than perfect mirror for the rest of your life? You could have saved yourself the trouble and bought a Meade mirror if you are willing to accept less than perfect!
 
Ken Hunter
 

Jason Hissong <jhissong@gmail.com> wrote:
I could also just mask it as my mirror is really an 8.125" mirror and it 
looks like just the outer 1/8 is turned down?



		
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