Looks like it should clear up.  Anyone going to the field tonight?

I picked up the b-cards and flyers for Saturday from Bruce last night.
  He also showed me his possible observing site and it's not too great
as long as Drugan's has their lights on.  He'll be checking with
Drugan's after he gets back from his weekend trip.

I have made 2 light shields that might help at the flying field, as
long as there's little wind.

I'll probably just observe from the backyard if no-one else is going
tonight.

Mike R.

Who You Gonna Call?

I made it up to the field last night for a couple hours. The wind died
down around sunset and, if you were dressed warm, it was a beautiful
evening...for a few hours.It would have been nice to tryout your light
shields as I was trying to pick up M74 which was due east and right
above the one yard light.

See you tonight.


--- In laxastro@yahoogroups.com, "Mike R." <fastsedan@...> wrote:
>
> Looks like it should clear up.  Anyone going to the field tonight?
>
> I picked up the b-cards and flyers for Saturday from Bruce last night.
>  He also showed me his possible observing site and it's not too great
> as long as Drugan's has their lights on.  He'll be checking with
> Drugan's after he gets back from his weekend trip.
>
> I have made 2 light shields that might help at the flying field, as
> long as there's little wind.
>
> I'll probably just observe from the backyard if no-one else is going
> tonight.
>
> Mike R.
>

A number of us met down at Riverside Park Saturday evening to share the
night sky with whoever should wander by and show some interest.

Mike R., Gordon S. Craig H., Bruce K. and myself showed around 20 very
appreciative people objects such as the moon, Jupiter, M13, and
Albireo.
One group of people I showed sites to were here from Seattle and they
expressed their appreciation a number of times and were even bragging
about what they were doing to somebody on their cell phone.They had no
clue what a globular cluster was before they came, but now they do and
they were quite amazed.

All in all it was a beautiful night. The heavenly stars were mostly
drowned out by street lights, but we still put stars in a number of
peoples eyes.

I still could not get diffraction rings (on Polaris anyway), but took
the club scope to the Astronomy Day session at Riverside Park.  Gordon
worked his magic with Craig's assistance (I believe on Vega) and lo
and behold there were diffraction rings.  I think they used my 15mm
Celestron eyepiece.

Of course I couldn't leave well enough alone and decided to make
another attempt at aligning the secondary.  I used an X-acto knife to
carve out the felt and cardboard where the spider lugs make contact
with the inside of the tube so that I could offset it just a little
more.  Also, I did something I had read about and I think Joe
mentioned, which is to use paper to block the reflection of the
primary, and to put behind the secondary so as to get a better view of
the secondary from the peep hole.  That worked like a charm and I
could see that I needed to raise the secondary (away from the primary)
more.  Now the focus hole reflection appears almost centered on the
secondary like in the collimation diagrams.

Are you still with me?  Okay, Phil came over with his laser
collimator, which can't be used on a closed tube to collimate the
primary, but we used it to align the secondary so that the dot was in
the new donut on the primary.  Then we adjusted the primary so that
the donut was centered on the reflection of the peep hole.  Then we
took it out and briefly caught a fast setting moon and also Jupiter.
Not too bad, but it obviously needed a star collimation.  As we were
trying to do this, it clouded over.  Oh well.

I think it should look pretty good now once it's star collimated, but
I'd really like to use some quality collimation tools on it.

Gordon, could you see if you can find the laser collimator?  I'd like
to at least play around with it.  I read that if you do a star
collimation, then note the error that you may or may not get with the
laser, you can get very accurate collimations with the laser by
reproducing the same error (this is an old metrology technique).

Later,

Mike R.

Wednesday night was clear with the moon at about 50 pct.  Did a rough
star collimation on Polaris, then got some pretty good views of the
Moon and Jupiter.  Could actually just barely make out the shadow of
one of the moons.  That's the best it's been since we pulled this
beast out of storage!  Saw the "sword" on the Moon that's mentioned in
one of this month's magazines.  Even with the Moon partially washing
out the sky, got a great view of M13 and got a pretty good view of
M81/M82.  Checked out the double cluster (below Cassiopia) and found
an unknown fuzzy somewhere above that.  As the Moon and Jupiter went
behind the tree line and Vega passed the zenith, I sought out Vega,
which I always have a problem lining up on with this big beast.  I
need to fix the Telrad asap.  Anyway, found it, and did another higher
power collimation which was definitely better than before.  The double
double still can't be split at x127 but it's clear at x183.  Couldn't
find the Ring this time.

Anyhoo, once I got the scope back in the garage, I checked the view
with the peep sight, and lo and behold, the peep hole is virtually
dead center in the donut on the primary.  Whoo hoo!

Hope to see you all at Bruce's; last I saw, Friday looked dicey but
Saturday was looking good.  Come check out the club scope!

Did I mention that I found on Astromart a picture of an original blue
Coulter 13.1.  Maybe this weekend I'll try to see if I can post
pictures here.

Later,

Mike R.

Mike and others - Chuck Groth, original owner of the club scope, built
a cardboard stop-down that really helped improve the contrast on bright
objects like the Moon, Jupiter, etc. It had an off-center hole about 3
or 4 inches in diameter. It seems strange to want to "chop-down" a
honking big scope to make it a small one, but it does 2 things. First,
it takes the effective f-ratio from 4.5 ish to around f/15. Second, a
lot of the time, the size of the cells in the Earth's atmosphere can
make a big scope less usefull than a smaller one. Try one and see what
you think.

Also, Chuck is the one who built the plywood holder for the scope's
Tuthill mylar solar filter. He was a contractor and did a nice job with
the two devices. The cardboard stop-down eventually got worn-out by
moving it around a lot.


Bob A

Hi

Did anyone see the PBS "Seeing in the Dark" special on Wednesday night? Was
very interesting, the only thing I would have liked to see more of was
actual amateurs and their equipment and their experiences. Other than that
it was very good.

Gene

See you Saturday!

The web page is at http://www.mnastro.org/

The menu on the left is easy to navigate.  Perhaps something there will
interest you, for personal or for LAAS interests.

The Rochester club will visit for the event Sep 22.  Perhaps our group
will visit some evening.

Regards, Red

One of the interesting items on the MN Astronomical Society web page
describes the ONAN observatory.  It is at http://www.mnastro.org/onan/

Regards, Red

Wow!  Their "imaging system" looks like it images in
all colors simultaneously or something.  Wonder who
their "benefactor" was.

Mike R.


      
________________________________________________________________________________\
____
Check out the hottest 2008 models today at Yahoo! Autos.
http://autos.yahoo.com/new_cars.html

Hi Mike and the group

I took a look at the Telrad and it's target mirror has a line melted
in it. It's cemented in so it's junk for the most part. I will look
for one  online that maybe broken that can be used for parts. I would
pickup the cost of the repair. If anyone knows of a place that sells
Telrad parts please post the URL. To get us by for the time being I
have an good Telrad for the club scope.

Thanks

Steve

Steve,

If the reticle is burnt out try
http://www.analyticalsci.com/Astronomy/Telrad/Telrad.htm

They have them for $5.00


>
> Hi Mike and the group
>
> I took a look at the Telrad and it's target mirror has a line melted
> in it. It's cemented in so it's junk for the most part. I will look
> for one  online that maybe broken that can be used for parts. I
would
> pickup the cost of the repair. If anyone knows of a place that sells
> Telrad parts please post the URL. To get us by for the time being I
> have an good Telrad for the club scope.
>
> Thanks
>
> Steve
>

Hi, Mike;

I stopped at the library this morning and read Nils Carlin's 2002
article on collimating Newtonians.

The Barlowed laser and the Cheshire sight are equivalent, except the
Cheshire requires a flashlight to operate at night.  Each one is
unaffected by misalignment of the focuser as far as bringing the axis
of the mirrors into alignment with the center of the focuser, at one
point, hopefully near the focal point of an eyepiece.

I'll buy the Cheshire from Orion and will share it with you for our
mutual experience.

I suspect my Orion laser collimator has a bad switch. When it first
failed to operate, repeatedly exercising the switch brought it to
life.  Saturday, that worked a few times, but it always failed again.
  Today, it is dead.  I've experienced that problem with other
miniature snap action switches.  I'll bring it next time we meet.
Maybe we can make a red pointer of it.

I will be out of the area next Wednesday and will miss the LAAS
meeting.  Please extend my regrets to the group.

Regards, Red

All,

The next meeting is Wed, Oct 10.  The room was already booked for something
Oktoberfest related on the 3rd.

Rick

---------- Original Message ----------------------------------
From: "red_haines" <WO0W@...>
Reply-To: laxastro@yahoogroups.com
Date:  Tue, 25 Sep 2007 23:55:25 -0000

>
>I will be out of the area next Wednesday and will miss the LAAS
>meeting.  Please extend my regrets to the group.
>
>Regards, Red
>
>
>

Steve,

If the reticle is burnt out try
http://www.analyticalsci.com/Astronomy/Telrad/Telrad.htm

They have them for $5.00

>
> Hi Mike and the group
>
> I took a look at the Telrad and it's target mirror has a line melted
> in it. It's cemented in so it's junk for the most part. I will look
> for one online that maybe broken that can be used for parts. I
would
> pickup the cost of the repair. If anyone knows of a place that sells
> Telrad parts please post the URL. To get us by for the time being I
> have an good Telrad for the club scope.
>
> Thanks
>
> Steve
>

I finally got around to looking at the online newlsetter. Kudos to
Craig for putting this together.

I do not recall getting this via email. Aren't they supposed to be
emailed out as well?

We have a request to join join the laxastro group from:

>The following person would like to join the laxastro group:
>Email address: rwfarley1960 <rwfarley1960@...>

>Comment from user:
>I'm an LAAS member. How does this group relate to LAAS?

Anyone know him/her?  I don't think we have any intention of limiting joining
the on-line group but I like to know who they are.  I know how fast on-line
groups can degenerate if membership is wide open...  I'll be sending a return
e-mail to tell what we use the yahoo group for.  And, if needed, a name.

Thanks, Rick

---------- Original Message ----------------------------------
From: "Phil Yehle" <rustyzip@...>
Reply-To: laxastro@yahoogroups.com
Date:  Tue, 25 Sep 2007 23:51:31 -0000

>Steve,
>
>If the reticle is burnt out try
>http://www.analyticalsci.com/Astronomy/Telrad/Telrad.htm
>
>They have them for $5.00
>
>
>>
>> Hi Mike and the group
>>
>> I took a look at the Telrad and it's target mirror has a line melted
>> in it. It's cemented in so it's junk for the most part. I will look
>> for one  online that maybe broken that can be used for parts. I
>would
>> pickup the cost of the repair. If anyone knows of a place that sells
>> Telrad parts please post the URL. To get us by for the time being I
>> have an good Telrad for the club scope.
>>
>> Thanks
>>
>> Steve
>>
>
>
>
>

Perhaps he's in Los Angeles or Louisiana? ;-)

Mike R.


--- Morrison <kb9tkg@...> wrote:

> We have a request to join join the laxastro group
> from:
>
> >The following person would like to join the
> laxastro group:
> >Email address: rwfarley1960
> <rwfarley1960@...>
>
> >Comment from user:
> >I'm an LAAS member. How does this group relate to
> LAAS?




      
________________________________________________________________________________\
____
Luggage? GPS? Comic books?
Check out fitting gifts for grads at Yahoo! Search
http://search.yahoo.com/search?fr=oni_on_mail&p=graduation+gifts&cs=bz

Well, that's what I'm thinking or it's an automated request that we don't want.

Just got another one. tomegad <tomegad@...>  They never add any comments
that help you know who they might be.

Rick
---------- Original Message ----------------------------------
From: Mike Rowlands <fastsedan@...>
Reply-To: laxastro@yahoogroups.com
Date:  Wed, 26 Sep 2007 07:00:22 -0700 (PDT)

>Perhaps he's in Los Angeles or Louisiana? ;-)
>
>Mike R.
>
>
>--- Morrison <kb9tkg@...> wrote:
>
>> We have a request to join join the laxastro group
>> from:
>>
>> >The following person would like to join the
>> laxastro group:
>> >Email address: rwfarley1960
>> <rwfarley1960@...>
>>
>> >Comment from user:
>> >I'm an LAAS member. How does this group relate to
>> LAAS?
>
>
>
>
>     
________________________________________________________________________________\
____
>Luggage? GPS? Comic books?
>Check out fitting gifts for grads at Yahoo! Search
>http://search.yahoo.com/search?fr=oni_on_mail&p=graduation+gifts&cs=bz
>
>

If they are not a member perhaps they should not have posting rights.

--- In laxastro@yahoogroups.com, "Morrison" <kb9tkg@...> wrote:
>
> Well, that's what I'm thinking or it's an automated request that we
don't want.
>
> Just got another one. tomegad <tomegad@...>  They never add any
comments that help you know who they might be.
>
> Rick
> ---------- Original Message ----------------------------------
> From: Mike Rowlands <fastsedan@...>
> Reply-To: laxastro@yahoogroups.com
> Date:  Wed, 26 Sep 2007 07:00:22 -0700 (PDT)
>
> >Perhaps he's in Los Angeles or Louisiana? ;-)
> >
> >Mike R.
> >
> >
> >--- Morrison <kb9tkg@...> wrote:
> >
> >> We have a request to join join the laxastro group
> >> from:
> >>
> >> >The following person would like to join the
> >> laxastro group:
> >> >Email address: rwfarley1960
> >> <rwfarley1960@...>
> >>
> >> >Comment from user:
> >> >I'm an LAAS member. How does this group relate to
> >> LAAS?
> >
> >
> >
> >
> >
______________________________________________________________________
______________
> >Luggage? GPS? Comic books?
> >Check out fitting gifts for grads at Yahoo! Search
> >http://search.yahoo.com/search?
fr=oni_on_mail&p=graduation+gifts&cs=bz
> >
> >
>

The laxastro yahoo group is set up now as: anyone can read the messages. You
have to be a member of the laxastro group to post messages. This is needed to
keep out the junk.

Although we don't have any (I don't believe) non-LAAS members as laxastro
members, I don't have any objection to anyone in the La Crosse area (interpret
area pretty wide, WI, MN, IA, maybe) being a laxastro member w/o being a LAAS
member.  Unless they have ties, ie, Bob, to the area, I just don't see why they
would want to join our group.  I would join one of the other yahoo groups or
Cloudy Nights or Astromart forums.

Rick
---------- Original Message ----------------------------------
From: "Phil Yehle" <rustyzip@...>
Reply-To: laxastro@yahoogroups.com
Date:  Wed, 26 Sep 2007 17:00:49 -0000

>If they are not a member perhaps they should not have posting rights.
>

Red and others - The University has a Cheshire and another collimating
device that I bought a long time ago. There were booklets with them.
Gordon would have access to them.


Bob

Bob,

Did this have the nice frame like the solar filter, or how was it
attached?  It was suggested that more than one hole would work also.
I'll have to do some research on this.

Thanks,

Mike R.


--- In laxastro@yahoogroups.com, "starman1944" <allen.robe@...> wrote:
>
> Mike and others - Chuck Groth, original owner of the club scope, built
> a cardboard stop-down that really helped improve the contrast on
bright objects like the Moon, Jupiter, etc....

Took the scope to Bruce's the other weekend, and everyone seemed happy
with the results so far.  Of course the moon was dominating, so good
deep space observing was out, but the double cluster, M13, and the
Ring looked pretty good.  Sam Sokolik was there with his Meade 90mm
Mak-Cass.  Red was there with his 10inch(?) dobson.  Red schooled Sam
on the use of Meade's Autostar.  Also there were Steve, J. Modahl, and
John B.  Bruce entertained us with many of his very creative projects.

Sometime after that, I looked at through the peep hole, and I don't
know if something settled, or I just hadn't checked it after my last
adjustments, but the secondary seemed to be off center again.

Oops, have to go pick up a burger at Features.

To be continued...

Mike R.

Okay, burger was good, mmmm. Anyway, Orion updated
their Lasermate collimators, and was closing out the
old ones at over 40 percent off.  Soooo, since I plan
on getting a truss scope, I picked up the old Deluxe
version for $46 shipped.  It seems to be well
"collimated", and with one layer of heavy duty Scotch
packing tape around the barrel, it fits fairly snugly
and consistently.  One thing to watch out for is that
you must set the "brake" on the rack and pinion
focuser in order to get consistent results.

Red and I have been discussing the barlowed laser
technique, which helps eliminate some of the errors
caused by slop in the laser/focuser mechanisms.  But
I've found, as I had hoped, you can get fairly
consistent results if you're careful, and with the
Deluxe Lasermate, YOU CAN SEE THE RESULTS AS YOU
ADJUST THE COLLIMATION SCREWS!!!  Whoo hoo!

So, now with the laser allowing the secondary and
primary to be easily adjusted, I started diddling
again.  I chiseled out more under the lugs on the side
opposite the focuser, and finally have a measurable
offset (about 16th inch).  Then I adjusted the
secondary up and down (from the direction of the
primary).  It is very tedious to do this without the
laser because you can't tighten the two nuts without
twisting the secondary, and you must go back and forth
from the peep hole to the wrenches.  The laser dot
shining on the mirror while you tighten, makes it a
snap.  I finally decided to shim the focuser a bit.
Found a couple very thin washers in my RC car toolbox
that worked well.

Okay, so after all that, the primary mirror's
reflection is still a bit off center in the secondary
when looking through the peep hole.  Also, the focus
hole reflection as seen from the peep hole is slightly
off center in the secondary.  But if you center either
one, the other gets further off!!!  So I've split the
difference and we'll have to see how the star
collimation turns out!

The only other things that could affect this are
(since I think I've tried EVERYTHING else multiple
times): 1. The donut on the mirror is slightly off.
2. The offset isn't far enough yet.  I'd have to make
some precise measurements of the primary to the
secondary, and the secondary to the focal point, in
order to calculate this.

Note also that it appears that the secondary might be
a little small according to some theoretical
calculations.

One final thing, per Gordon's suggestion (and similar
info as seen on the internet), I put a stack of CDs on
the center bolt.  I also put some Zymol car wax on the
formica on the base and metal altitude bearings.  This
is a natural carnuba wax that is currently $49 for
about 16 oz.  Nothing but the best for the club!  The
azimuth is better now, but the altitude is almost too
slick!  Can't wait for clear skies!!

Later,

Mike R.



________________________________________________________________________________\
____
Building a website is a piece of cake. Yahoo! Small Business gives you all the
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*For  you interest. Regards, Red

Finland's biggest astronomical association, Ursa, says that a light
phenomenon seen over much of northern and eastern Finland on Friday
night was a meteor -- the brightest seen in the country in more than 30
years. *

The editor of the organization's journal <http://www.avaruus.fi/>, Marko
Pekkola, says it was a superbolide, a fireball more than 100 times
brighter than a full moon.

The fireball was apparently caused by a space rock striking the
atmosphere over Northern Ostrobothnia and then exploding over Finland.
Ursa <http://www.ursa.fi/english.html> says the rock may have weighed
some 200 kilogrammes. However it was not clear on Saturday whether any
meteorites fell to the ground.

The dazzling 'shooting star' spurred worried telephone calls to
emergency centres in various parts of Finnish Lapland, as far apart as
Kemi, Enontekiö and Ivalo.

/YLE, Tähdet ja avaruus/

Mike - I think the multiple holes are for focusing for ccd imaging.
Something like a Hartmann mask.

No, the aperture stop-down didn't have any frame. It just kind of
bent over the top edge of the tube to keep it from falling. It needs
to be off-center to avoid the secondary mirror, but not too close to
the edge as the outer parts of a mirror generally have more
aberrations than the inner parts.


Bob



--- In laxastro@yahoogroups.com, "Mike R." <fastsedan@...> wrote:
>
> Bob,
>
> Did this have the nice frame like the solar filter, or how was it
> attached?  It was suggested that more than one hole would work
also.
> I'll have to do some research on this.
>
> Thanks,
>
> Mike R.
>
>
> --- In laxastro@yahoogroups.com, "starman1944" <allen.robe@> wrote:
> >
> > Mike and others - Chuck Groth, original owner of the club scope,
built
> > a cardboard stop-down that really helped improve the contrast on
> bright objects like the Moon, Jupiter, etc....
>