From: "Mike and Sara" 
To: 
Reply-To: "Mike and Sara" 


Hello!

    I met Jane Houston Jones, president of the Astronomial Association of
Northern California, last year, here in Alice Springs for the Leonids
observation.  I was in the midst of grinding my fist 4.25 inch mirror for
my children.  I described my frustrations with the grinding and polishing
errors I encountered, since no one else in my club makes their own mirrors.

    Anyway, she described her long career of making mirrors with the Jon
Dobson method.  She described herself as a tele-evangelist, an evangelist
to get people to use their telescopes.

    She described how she made 10 inch mirrors in a day, 4 hours to rough, 4
hours to fine grind, and 4 hours to polish.

     When I asked her about testing, etc. to make sure of the figure, she
said she regularly obtains 1/4 wave optics by slightly deepening the center
during the final stage of fine grinding, then polishing and star testing!

    To me, as a Newbie, such skill is far down the road, but I can
understand the letters to date about the philosophy of John Dobson about
getting making telescopes to be used.  Jane's comments underscored to me
what a skilled worker can do, though at my newbie level, I want as many
aids as I can, both to ensure quality optics, but also to learn, and
perhaps, just to have fun with the hobby or mirror making.

Best regards,

Mike
----- Original Message -----
From: "DAVID K OESTREICH" 
To: "Michael Burr" ; "ATM shore"

Sent: Saturday, December 21, 2002 7:45 AM Subject: Re: ATM HELP! mirror
making crossroads


>
> > I'm not suggesting that he would shrug off the TDE on your
12.5" mirror,
> but
> > overall my point is that he seems more intent on getting people at the
> > eyepiece than he is on creating the perfect telescope. Of course from a
> > practical standpoint, an eight-foot telescope won't be all that
> accessible,
> > so even Mr. Dobson would have to agree that you haven't reached the
> desired
> > destination.
> >
> quite the contrary John was perfectly happy with the idea of an F8 scope.
> He seems to favor longer focal lengths. There were some very fundamental
> differences in his thinking and what most folks are doing today. Mirror
> cells made of cardboard and friction focusers made of sink drains is
hi-tech
> according to John.
> Truss scopes are completely out according to him. Give him carboard tube
any
> day.
> Don't expect lab grade equipment out of one of his classes. The focus is
to
> build a sidewalk telescope for the general public to use. The vast
majority
> of us probably build scopes (or at least that special scope) for our own
> use.
> Making the mechanism idiot proof is not our principal goal (not mine at
> least) making one that work exceedingly well
> is.
> I have a 10" Meade that frankly kicks ass but I would like a bigger light
> bucket and also wanted to make one myself.
> Call it the pride of creation. My goal wasn't to save money (which I
didn't)
> It was to say when it was all over....
> I made this... kind of neat huh.
> -Karlo
> ----- Original Message -----
> From: "Michael Burr" 
> To: "ATM shore" 
> Sent: Friday, December 20, 2002 8:49 AM
> Subject: Re: ATM HELP! mirror making crossroads
>
>
> >
> > One point maybe worth considering, vis-a-vis John Dobson, ... I gather
> that
> > the main purpose of his astronomy evangelism is to get people out there
> > observing. The telescope making part of it doesn't seem to really be his
> > main interest, in spite of the fact that it's what he's famous for
> > spreading. If you watch his video, it's obvious that he's anything _but_
> > fastidious in things like testing and achieving a perfect surface.
Instead
> > what he's trying to make is a telescope that simply works.
> >
> > I'm not suggesting that he would shrug off the TDE on your
12.5" mirror,
> but
> > overall my point is that he seems more intent on getting people at the
> > eyepiece than he is on creating the perfect telescope. Of course from a
> > practical standpoint, an eight-foot telescope won't be all that
> accessible,
> > so even Mr. Dobson would have to agree that you haven't reached the
> desired
> > destination.
> >
> > Buck up! Learning is fun if you see it as an opportunity to gain
> knowledge,
> > understanding and skills. It may be hard, but in the long run every
> mistake
> > pays off if you learn something from it.
> >
> > Best Regards,
> > Michael Burr
> >
>
>

--- BBBS/NT v4.00 MP