I've been talking to Rick Singmaster about my new scope he's building,
Rick has had
problems getting a "good" secondary for my 20" scope. He has ended up
buying four secondaries for my scope because the first three were not up
to his performance standards. The first three had too much astigmatism.
This would limit the fine primary mirror's performance. We both agreed
that many scope owners today probably have too much astigmatism in their
secondariy mirrors since he acknowledges that many secondaries are being
sold with this deficiency. Most amateurs just don't know that they do
have a substandard secondary mirror. All attention these days is to the
primary mirror's size and optical accuracy. I takes a bit of expertise
to notice seconday mirror astigmatism which could be compromising the
whole system wavefront accuracy.
Peter
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From: "Rick Singmaster" <starmaster@No-Spam>
To: "Peter Natscher" <peter@No-Spam>
Subject: Battery Power
Date: Fri, 14 Jan 1999 10:54:53 -0600
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Peter,
We will get the scope shipped out via UPS ground Mon. or Tue at the latest.
There will be 7-8 cartons. There are lots of scopes out there with bad
secondary mirrors. Most folks just presume that if they have soso
performance it must be the primary mirror. I have rejected secondary
mirrors nearly 10 to 1 as compared to rejected primary mirrors.
Later,
Rick
----------
> From: Peter Natscher <peter@No-Spam>
> To: Rick Singmaster <starmaster@No-Spam>
> Subject: Battery Power
> Date: Friday, January 14, 1999 10:21 AM
>
> Rick,
>
> Sorry for all the trouble you've had with getting a good secondary
mirror.
> Hope you're feeling better now. Makes me wonder how many other's have
> deficient secondaries in their scopes and don't even know about it.
Experts
> like you really make the difference in bulding high quality telescopes.
>
> Go ahead and send me the scope. I'm around the house regularly during the
day
> and I know the local UPS deliverer, here. Are you using UPS? My office is
1/4
> mi. away from my house. How many boxes do you think will be delivered to
me?
>
> Make sure to deliver via UPS to my house at:
>
> Peter Natscher
> 210 Graham Street
> Jacksonville, OR 97530
>
> My billing mail address (USPS) is:
>
> P. O. 1800
> Jacksonville, OR 97530
>
> Regards,
>
> Peter
>
>
> Rick Singmaster wrote:
>
> > Peter,
> > Have done extensive testing of the scope. I replaced TWO secondary
> > mirrors!!
> > Both were astigmatic. Geez, they about drove me nuts. Tonight the temps
> > have dropped to about freezing and the scope is performing fine. All
the
> > problems I had were with secondary mirrors!!!!! I am using only
> > individually tested and certified secondary mirrors and even
then.........
> > The primary mirror is superb in this scope. The tracking and go to are
very
> > good. I will tell you right now, if you dont like this mirror, send it
back
> > and I will put in it my own scope. :-)) I have finally eliminated the
bad
> > secondary mirrors and now have a third one in there which is fine.
These
> > are the first secondary mirrors I have had a problem with since I have
been
> > using the United Lens secondary mirrors. The damn things cost me nearly
> > $300.00 Ea.!!! And they want to argue when I tell them I have a bad
one.
> > Christ, I dont know how Obsession, Starsplitter, Tectron or anyone else
can
> > get by sending out scopes without testing them.
> > I test each one and buy the best components and still have problems
about
> > 1/4th of the time. Oh well, I am very particular about performance and
I
> > guess the untold extra hours I spend testing ALL my scopes is going to
pay
> > off in the long run.
> > At any rate, we are going to pack the scope up probably tomorrow. We
will
> > charge your card in the morning and will NOT ship the scope untill we
hear
> > from you. Want to be sure you will be home when it arrives. Drop me an
> > email or call and we will get it out of here.
> > I really appreciate your patience. On top of everything else, I have
been
> > sick, very sick, with the flu for about two weeks and am finally
getting
> > over that.
> > Thanks,
> > Rick
> >
> > ----------
> > > From: Peter Natscher <natscher@No-Spam>
> > > To: Rick Singmaster <starmaster@No-Spam>
> > > Subject: Battery Power
> > > Date: Saturday, January 01, 1999 10:53 PM
> > >
> > > OK
> > >
> > > Peter
> > >
> > > Rick Singmaster wrote:
> > >
> > > > Peter,
> > > > I will be testing the scope in temps below freezing later in the
week
> > when
> > > > I get the drive installed. I suspect it will be fine as it went
through
> > the
> > > > wide drop the other night. I will know for sure when my feet are
> > freezing.
> > > > :-) I will make sure BEFORE I charge your card and ship it.
> > > > Thanks, will be in touch late this next week/weekend.
> > > > Rick
> > > >
> > > > ----------
> > > > > From: Peter Natscher <natscher@No-Spam>
> > > > > To: Rick Singmaster <starmaster@No-Spam>
> > > > > Subject: Battery Power
> > > > > Date: Saturday, January 01, 1999 9:45 PM
> > > > >
> > > > > Hi Rick,
> > > > >
> > > > > That's great news about your approval of the 20"er you're making
for
> > me.
> > > > If
> > > > > you feel OK with everything, then by all means send it out to me.
> > Charge
> > > > my
> > > > > "balance due" to the same VISA card of mine that you charged the
> > first
> > > > $4,000
> > > > > to last September.
> > > > >
> > > > > One question: Will the optics (20" and secondary) properly handle
> > > > observing in
> > > > > 25¡F-30¡F night time temperatures? That's what the temps are in
> > winter
> > > > around
> > > > > here.
> > > > >
> > > > > Peter
> > > > >
> > > > > Rick Singmaster wrote:
> > > > >
> > > > > > Peter,
> > > > > > I changed the secondary mirror in the scope and I observed with
it
> > for
> > > > > > about 6 hours a couple of nights ago. I saw no sign of the
strain
> > which
> > > > I
> > > > > > thought might ne there from an earlier session. I have used it
a
> > couple
> > > > of
> > > > > > shorter sessions and didnt see any proplems. I had a 10" f/6.0
and
> > a
> > > > > > 14.5"f/4.5 set up with it. The 14.5" is one a friend of mine
owns
> > and
> > > > is
> > > > > > superb. The 20"er outperformed both of those scopes on ALL
objects,
> > > > > > including the planets and trapezium stars during the entire
> > session.
> > > > The
> > > > > > temp started out in the mid 60's and dropped to about 38
degrees
> > by 6
> > > > > > hours later. This is the kind of temp swing I had been waiting
for
> > to
> > > > > > observe for sure how the mirror was going to perform.
> > > > > > At this point, I strongly suspect the brief image degradation I
saw
> > > > during
> > > > > > one only other ocassion may have even been a very brief
"normal"
> > change
> > > > on
> > > > > > figure during a short equilibration period. This is something
which
> > > > does
> > > > > > occur with larger aperture once in awhile and it usually lasts
for
> > only
> > > > a
> > > > > > very few minutes, especiall if a sudden cold breeze come up.
> > > > > > Bottom line, the mirror is a superb performer and I feel
> > comfortable
> > > > > > sending the scope on out to you for your use. IF you see
anything
> > which
> > > > is
> > > > > > troublesome to you, we will replace the mirror as indicated at
no
> > cost
> > > > to
> > > > > > you. I still need to install the SkyTracker and test the scope
> > again
> > > > with
> > > > > > it running and will get that done next week. I believe after
having
> > > > > > observed with this mirror now several times and comparing it to
> > other
> > > > > > scopes you will be very pleased with the high contrast
planetary
> > and
> > > > deep
> > > > > > sky images it provides. I was not able to push the power much
over
> > 200x
> > > > on
> > > > > > the planets due to the seeing conditions but the defocused
stars
> > test
> > > > shows
> > > > > > the mirror to be superb in every way, including smoothness. It
is
> > the
> > > > > > smoothness of this optic which will allow it to go to 1000x
without
> > any
> > > > > > problem on the rare night you get that kind of seeing.
> > > > > > Let me know if this is satisfactory with you.
> > > > > > Thanks,
> > > > > > Rick
> > > > > >
> > > > > > ----------
> > > > > > > From: Peter Natscher <natscher@No-Spam>
> > > > > > > To: Rick Singmaster <starmaster@No-Spam>
> > > > > > > Subject: Battery Power
> > > > > > > Date: Tuesday, December 28, 1999 9:58 AM
> > > > > > >
> > > > > > > Rick,
> > > > > > >
> > > > > > > Thanks for your reply about the battery and mirror. Go ahead
and
> > keep
> > > > the
> > > > > > > scope as long as you need to for checking things out. The
weather
> > > > here
> > > > > > will
> > > > > > > leave me little time to observe, probably until March. I'm
only
> > able
> > > > to
> > > > > > get
> > > > > > > diffraction images with my 8.5" Mak-Newt., nothing larger.
The
> > nights
> > > > > > here
> > > > > > > are going down to 24¡F with a lot of ice. Your payment terms
are
> > fine
> > > > > > with me.
> > > > > > >
> > > > > > > And, I will accept your offer of the extra batteries. Thank
you.
> > > > > > >
> > > > > > > Happy New Year 1999 to you and your family!
> > > > > > >
> > > > > > > Peter Natscher
> > > > > > > Jacksonville, Oregon
> > > > > > >
> > > > > > > Rick Singmaster wrote:
> > > > > > >
> > > > > > > > Peter,
> > > > > > > > We include 2 ea. 7 amp hr batteries. The scope will
normally
> > run
> > > > about
> > > > > > 8
> > > > > > > > hours on 1 battery. We sell the batteries for $25.00 ea.
and I
> > > > would
> > > > > > just
> > > > > > > > add a third one as opposed to messing with an external
battery
> > and
> > > > > > cables.
> > > > > > > > You can probably find the batteries in you area, if not, we
> > stock
> > > > them.
> > > > > > > > Forget that, because of the delay to you, we will just
furnish
> > a
> > > > 3rd
> > > > > > > > battery with the scope at no charge.
> > > > > > > > I have replaced the secondary in the scope which was bad
and
> > have
> > > > > > observed
> > > > > > > > with it for a couple of short sessions again. The images
were
> > fine
> > > > but
> > > > > > I
> > > > > > > > need to do a several hour session when the temps are
falling. I
> > am
> > > > > > > > beginning to think the primary mirror may be OK, but just
am
> > not
> > > > sure
> > > > > > yet.
> > > > > > > > If the scope continues to perform without exhibiting the
signs
> > of
> > > > glass
> > > > > > > > strain I saw the first night, I will let you know. I may go
> > ahead
> > > > and
> > > > > > ship
> > > > > > > > it to you with assurance that IF the mirror acts up again,
it
> > will
> > > > be
> > > > > > > > replaced at no cost to you. I just need another long night
with
> > it.
> > > > I
> > > > > > will
> > > > > > > > let you know. This mirror is extremely smooth and the
> > performance
> > > > is
> > > > > > superb
> > > > > > > > for the majority of the times I have used it. Carl has
> > replacement
> > > > > > glass
> > > > > > > > either there or expected in shortly so its not going to be
very
> > > > long
> > > > > > either
> > > > > > > > way. Tonight looks like the kind of night I have been
waiting
> > for,
> > > > > > temps
> > > > > > > > upper 50s daytime , falling to freezing by midnight. If it
> > performs
> > > > > > fine, I
> > > > > > > > will plan on shipping it sometime next week. If I have any
> > > > suspicions
> > > > > > at
> > > > > > > > all, I may want to ship it anyway and let you use it untill
a
> > > > > > replacement
> > > > > > > > mirror is completed. I would leave a $1000.00 balance on
your
> > > > account
> > > > > > for a
> > > > > > > > period of 60 days or untill you recieve a replacement
mirror
> > and
> > > > test
> > > > > > it.
> > > > > > > > This would be only in the event the scope performs well on
the
> > next
> > > > > > long
> > > > > > > > session. That way, you will have adequate time in you
> > conditions to
> > > > see
> > > > > > if
> > > > > > > > it is absolutly ok with assurance that we are backing up
our
> > > > warranty.
> > > > > > > > If the mirror acts up clearly tonight, I just will wait
untill
> > I
> > > > get
> > > > > > > > another mirror in here so I can retest the entire system.
There
> > > > just
> > > > > > isnt
> > > > > > > > much else I can think of to do.
> > > > > > > > Thanks,
> > > > > > > > Happy New Year!!
> > > > > > > > Rick