When telescopes went "Tick-Tock".

Hi--
When "clouded out" I like to read.
I was in the public library in my town and found a copy of "Out of
the Darkness: The Planet Pluto" by Clyde Tombaugh (with Sir Patrick
Moore) Stackpole publishers, 1980.
It describes the difficulties inherent in conducting a planet search
(basically photographing several times every star field in the ecliptic
(and then some) and manually blinking each and every star down to
magnitude 15). That, my friends, is a lot of stars on those 14"x17"
plates, some requiring 2.5 hr manually guided exposures. I tried 30
minutes once and my life passed before my eyes.
If you happen to be in a used book store or public library, it's well
worth a read for its insights into the operation of a 20th century
observatory, its descriptions those involved, and the technical
(scope-talk) details of the equipment, especially the 13 inch and
associated cameras and techniques used in the discovery of Pluto.
For me, it puts late 19th and early 20th century astronomy into a
different perspective.

UB

UB,

When I was working at Lick a few decades ago I took exposures of 90
minutes with a 12 inch refactor and know what the life before your eyes
is about. While at the Santa Cruz campus, I stopped by the photoshop to
get some "free prints" as blemished prints were tossed in the trash.

I obtained a copy of, if I remember, M42 that had 14 or more diffraction
spikes visible on the stars. I asked the resident observer what that was
about and he said that early plates taken with the crossley(sp?)
reflector used piano wire to suspend the plate at focus.

Now that's what I call motivation to guide to your best.

Technique like that is no more...

I have no idea how a focus run was done, should of asked.



Dan



Uncle Bob wrote:

Hi--
When "clouded out" I like to read.
I was in the public library in my town and found a copy of "Out of the
Darkness: The Planet Pluto" by Clyde Tombaugh (with Sir Patrick Moore)
Stackpole publishers, 1980.
It describes the difficulties inherent in conducting a planet search
(basically photographing several times every star field in the ecliptic
(and then some) and manually blinking each and every star down to
magnitude 15). That, my friends, is a lot of stars on those 14"x17"
plates, some requiring 2.5 hr manually guided exposures. I tried 30
minutes once and my life passed before my eyes.
If you happen to be in a used book store or public library, it's well
worth a read for its insights into the operation of a 20th century
observatory, its descriptions those involved, and the technical
(scope-talk) details of the equipment, especially the 13 inch and
associated cameras and techniques used in the discovery of Pluto.
For me, it puts late 19th and early 20th century astronomy into a
different perspective.

UB

Uncle Bob writes:

I was in the public library in my town and found a copy of "Out of
the Darkness: The Planet Pluto" by Clyde Tombaugh (with Sir Patrick
Moore) Stackpole publishers, 1980.

A very good read, indeed. My own copy is nearly worn out.

It describes the difficulties inherent in conducting a planet
search (basically photographing several times every star field in the
ecliptic (and then some) and manually blinking each and every star
down to magnitude 15). That, my friends, is a lot of stars on those
14"x17" plates, some requiring 2.5 hr manually guided exposures. I
tried 30 minutes once and my life passed before my eyes.

I was reminded of that book and the long cold hours that Tombaugh
spent manually guiding searching the outer solar system when, a couple
of weeks ago, I caught a Kuiper Belt object (Orcus) with my simple
"cookbook" CCD camera without any guiding at all. Orcus is a hundred
times fainter than Pluto and beyond anything Tombaugh could have
detected with the equipment available to him. Life is not fair.

pej
--
Per Erik Jorde

On Tue, 05 Apr 2005 21:54:15 -0700, Uncle Bob
wrote:


Hi--
When "clouded out" I like to read.
I was in the public library in my town and found a copy of "Out of
the Darkness: The Planet Pluto" by Clyde Tombaugh (with Sir Patrick
Moore) Stackpole publishers, 1980. ...

On a related note, it's worth a visit to Flagstaff to see the Lowell
Observatory. The Pluto-discovery telescope is on the tour, in addition
to the huge refractor that Lowell used to study Mars. There are a lot
of precious artifacts from this period of astronomy on display...the
very first spectrometer for instance and the 'blinker' machine used to
discover Pluto from the plates taken by the telescope.

The Grand Canyon and Berringer Meteor Crater are close to Flagstaff in
addition to some extinct volcanoes and native ruins to the north
(which I missed). You can pretty much cover all these sites in a short
period of time, say 2 or 3 days. Makes for a great enlightening
vacation.

-Drew

"Uncle Bob" wrote in message
g.com...

Hi--
When "clouded out" I like to read.
I was in the public library in my town and found a copy of "Out of
the Darkness: The Planet Pluto" by Clyde Tombaugh (with Sir Patrick
Moore) Stackpole publishers, 1980.
It describes the difficulties inherent in conducting a planet search
(basically photographing several times every star field in the ecliptic
(and then some) and manually blinking each and every star down to
magnitude 15). That, my friends, is a lot of stars on those 14"x17"
plates, some requiring 2.5 hr manually guided exposures. I tried 30
minutes once and my life passed before my eyes.
If you happen to be in a used book store or public library, it's well
worth a read for its insights into the operation of a 20th century
observatory, its descriptions those involved, and the technical
(scope-talk) details of the equipment, especially the 13 inch and
associated cameras and techniques used in the discovery of Pluto.
For me, it puts late 19th and early 20th century astronomy into a
different perspective.

UB


It has to be three or four years now that I started a collection of
books. Quite a few of the famous beginner books, read them all. Even more
of the intermediate books on Astronomy and Particle physics, read them all.
And quite a few on specific Astrophysics and other specific physics, read
them all. My current library isn't large, last count was like 75-80 books
with the oldest being only in the sixties and the newest being, I think,
early nineties. I understand that your topic is the fascination of the
workings of scope and equipment of years ago but I think this fits in close
to the same topic.. I'm scraping the bottom of the barrel and it's starting
to look like I'll have no choice but to grab an entry level minimum wage job
but when I get something that resembles an income I'll start adding more
books to my library and reading and reading and reading some more. There
are some odd questions that I have here and there that need the speed and/or
resources of the net but nothing can compare to the information contained in
a local library, even when they are as small as mine.
--
Michael A. Barlow
who would love to find a position at an observatory or science center, even
at entry level.

Dan, that is the 12 inch Clark?
That telescope was installed with a band drive, nothing real exotic but
somewhat unusual, using a band of steel to drive between axles.
These drives have been discussed lately, without any input from someone who
actually used one.
It is unclear if that original Clark drive was still in use during the
1960s era.
Do you have any recollections? How well it worked?
Or anything to say about that very venerable telescope, now in storage?
thanks
Peter

Dan Mckenna wrote
When I was working at Lick a few decades ago I took exposures of 90
minutes with a 12 inch refactor and know what the life before your
eyes is about.

=============================================
Peter Abrahams telscope.at.europa.dot.com
The history of the telescope and the binocular:
http://home.europa.com/~telscope/binotele.htm

Peter please find my comments in line

Peter Abrahams wrote:
Dan, that is the 12 inch Clark?
Yes
That telescope was installed with a band drive, nothing real exotic but
somewhat unusual, using a band of steel to drive between axles.
These drives have been discussed lately, without any input from someone who
actually used one.
It was twenty some years in the past and even though I remember the
sounds and the smell of the dome on a warm summer night i may not be to
clear on the details

It is unclear if that original Clark drive was still in use during the
1960s era.
Do you have any recollections? How well it worked?
Or anything to say about that very venerable telescope, now in storage?
thanks
Peter

I would take 90 minute exposures with a V filter for the objects I was
monitoring and would of gone longer but the drive was sector based which
means that you move the sector drive to the east end of the travel and
it would track from that position for 90 minutes. If I remember it was
factory equipment for the time and that meant weight driven.

I could be wrong and it was a motor however I seem to remember the
weight on a cable.

I think guiding was via a tangent arm that was worm driven by twisting
a knob that was coaxial to the axis release clutch.

After Lick I was at UCLA and we had a 6 inch refactor that was not as
old bet was up graded to a electric motor drive. personally I though it
should have not been modified...however I might be mistaken
so many telescopes... so many nights

The Clark was originally ordered by Argentina ?? and they didn't pay so
James Lick obtained it.

It is a fabulous telescope that had received tender loving care by the
Lick staff. It provided the best view of jupiter I have yet to see using
a V filter.

The drive was smooth and didn't jump and the guide errors were easy to
correct for.

L. Aller told me that he was observing mars with a fellow grad student
on the 12 (1930's) and the 36 inch observers invited them to look at
mars as the canali where very distinct that night.

He said it was an awkward moment because the 36" observers wanted to
know if the saw the features.

Aller told me the 12 inch views were much better and they didn't see the
markings as described by the 36" observer although he didn't say it to them.

When pressed, they confessed that they didn't see the markings the 36'
observers told them that there was two types of eyes.

One could see faint objects and he other could see fine detail.
L. Aller and his fellow grad students were told that they had eyes
for faint objects and to take that into account in their quest for
an astronomical career.

Aller told me they were to full of them selves to see clearly.


What a joy to use and a much more interesting telescope than a modern
wizbang robodrive telescope.

Back to my wizbang,robodrive, sit in a chair, watch three computer
monitors, listen to the fans, push the button and never see or smell the
sky.

Hey, you don't get constipated running up and down the stairs all night
long and that makes a difference in the long run. On the flip side
in winter the magic is gone in a few minutes and get me to a warm room.

The other thing about the 12 is that it would go below the horizon
and looking across the bay at the city was a gas. I am told that they
did that back in the big quake to see what the smoke was about.
I liked watching venus set as one could see the development of the green
flash.

Thanks for the memories

Dan







Dan Mckenna wrote

When I was working at Lick a few decades ago I took exposures of 90
minutes with a 12 inch refactor and know what the life before your
eyes is about.


=============================================
Peter Abrahams telscope.at.europa.dot.com
The history of the telescope and the binocular:
http://home.europa.com/~telscope/binotele.htm

On Wed, 06 Apr 2005 22:24:35 -0700, Dan Mckenna wrote:

After Lick I was at UCLA and we had a 6 inch refactor that was not as
old bet was up graded to a electric motor drive. personally I though it
should have not been modified...however I might be mistaken
so many telescopes... so many nights

That telescope is the same as the one at Mount Wilson Observatory. It is
commonly accepted that the lens is by Brashear (who provided most of the
small optics in the observatory's early years) but the lens cell is labeled
otherwise so there is some controversy. The mount is Warner and Swasey.
The 6-inch at Mt. Wilson is currently out of the dome where it was
installed for use in the solar program around 1914 but it will be put back
in its dome later this year. It is still operated by the original
weight-driven clock drive. The Snow telescope that we use for the CUREA
program each year is also still driven by its similar weight-driven drive.
The 100-inch was still perated by it's falling weight drive when I first
used it in the 1980s. *That* governor was something to see in action.
It's still there but idle.

Mike Simmons

Hi Mike,

I seem to remember someone telling me these were in a class of "Garden
Telescopes" that were vogue with the upper crust at one time.
Is that a memory error on my part or true ?

Dan


Mike Simmons wrote:
On Wed, 06 Apr 2005 22:24:35 -0700, Dan Mckenna wrote:


After Lick I was at UCLA and we had a 6 inch refactor that was not as
old bet was up graded to a electric motor drive. personally I though it
should have not been modified...however I might be mistaken
so many telescopes... so many nights


That telescope is the same as the one at Mount Wilson Observatory. It is
commonly accepted that the lens is by Brashear (who provided most of the
small optics in the observatory's early years) but the lens cell is labeled
otherwise so there is some controversy. The mount is Warner and Swasey.
The 6-inch at Mt. Wilson is currently out of the dome where it was
installed for use in the solar program around 1914 but it will be put back
in its dome later this year. It is still operated by the original
weight-driven clock drive. The Snow telescope that we use for the CUREA
program each year is also still driven by its similar weight-driven drive.
The 100-inch was still perated by it's falling weight drive when I first
used it in the 1980s. *That* governor was something to see in action.
It's still there but idle.

Mike Simmons

Hi Mike,

I seem to remember someone telling me these were in a class of "Garden
Telescopes" that were vogue with the upper crust at one time.
Is that a memory error on my part or true ?

Dan

Hi Dan,

I hadn't heard that. They'd be awfully nice "Garden Telescopes", wouldn't
they? :-) The one at Mt. Wilson was definitely made for professional use
for the solar program (monitoring the sun for active regions for the tower
telescopes to study in more detail) but I don't know if it was actually
part of a regular production run sold to amateurs as well as professionals.

Mike Simmons