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1995-05-02
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Stellafane 1990: A First Timer's View
I just returned from a weekend at the Stellafane convention in Springfield,
Vermont. This was my first time at this telescope makers' convention and
star party, and it was a great experience: informative, entertaining,
frustrating, inspiring, and fun. In this article I'll try to give you an
idea of what it was like for me. Hint: I'll be back next year.
THE DAY BEFORE:
It's been a busy week at work. At 4:30pm I take delivery of a new circuit
module I was supposed to start testing last Monday morning. The developer
plugs it in and leaves. I fire up the unit and run a simple test to see if
the problem bugging me all week is history. It isn't. I am.
After dinner I stand in the midst of an explosion of equipment, both
astronomical and photographic. I know what I want to take with me. I just
can't figure out how to pack it compactly enough to avoid hiring sherpas.
I settle on a two case dense pack of camera lenses, bodies, eyepieces and
accessories, a third for the Questar 3.5", a duffle bag and a back pack.
I crawl into bed late and dream of bigger bags.
DAY ONE:
I drag myself out of bed at 5:00am and start my final preparations, eat
breakfast, and discard enough of the items I packed the night before to
leave one bag at home. I get an early start to beat rush hour traffic and
drive the 50 miles to the NJAA observatory where my travelling companions
will pick me up. They arrive on time, I pile in with my stuff, and we drive
40 miles back toward my house to pick up the final member of the group.
Oh well.
The trip north from New Jersey to Vermont is scenic and pleasant, especially
since I don't have to drive. I discover that amateur astronomers have a love
of pets, especially tropical fish. We pass a bus full of prisoners going "up
the river". A guard stands at the front, forward of the white line. ("What
are they gonna do, send me to prison?") A grey Isuzu Trooper zooms by us in
the left lane. "Hey, that was Lenny!" exclaims someone in the van, referring
to another club member. We pull our van into the left lane, accellerate to
catch the Isuzu, and pull up close behind, flashing our bright beams. The
Isuzu pulls over. We pull along side. It isn't Lenny. He isn't amused.
We roll into White River Junction, Vermont around 4:30pm, divvy up the rooms
at the Susse Chalet and make our obligatory phone calls home. The rooms are
simple but neat, phone calls are not surcharged (much), and the cable TV has
C-SPAN. We visit a Howard Johnson's for dinner and leave for Springfield. A
car allegedly piloted by Walter Scott "Scotty" Houston whizzes by in the left
lane, but we decide against flashing our lights. (It wasn't him anyway. He was
in Europe.) We arrive at Stellafane in an intermittent rain. Familiar faces
from NJ's AAI take our registrations and wave us on, smiling. We're here.
We park and begin to wander around, greeting friends and acquaintences from
other clubs, as well as our own. Eventually we gravitate toward the new
"amphitheater", a concave hillside focusing on an improvised stage where
the evening's talks will be held. The air is still and humid, and begins to
fill up with cigarette smoke (an unfortunately common addiction among my
comrades). The skies begin to clear as the sun sets and the talks begin.
Friday evening's talks are short and informal, a kind of living "Gleanings"
column. The slide shows are easily visible, but frequently too bright. The
27" TV is a dot burning a hole in my retina. There are a thousand engineers
gathered around, but no one can figure out how to fix a VCR stuck on high
speed, and Roger Tuthill's talk is derailed until later. Peter Ceravolo tells
us how to aluminize our own mirrors. Slides of Jupiter and Io are choreographed
to music. I lean back and gaze at the gathering stars of the summer Milky Way.
We leave the amphitheater before the talks conclude and head back to the van.
I depend on a companion with a bright red flashlight for guidance, since my
timid red light is too dim to be useful and I seem to lose my equilibrium in
the dark. At the van, the youngster in our group is already asleep. The rest
of us haul out our equipment for a night of observing under dark but dewy skies.
I set up my Questar and check Saturn low in the south. The seeing is poor,
but that doesn't matter since my objective is piggyback astrophotography
using the telescope as a tracker. I particularly want a shot at Comet Levy.
I set up the piggyback mount and grope for my camera equipment. I mate the
camera body (2.5 lbs) to the 80-200mm f/2.8 lens (3.5 lbs) and mount it on
top of the Questar (7 lbs), which instantly slams into position to view the
zenith. I balance the assembly and point it toward Saturn, but a look into
the camera finder shows the silouette of a moth which had somehow gotten
inside the camera. I undo the lens but the moth is nowhere to be found, so
I remount the lens and point the polar aligned scope in the general direction
of the North American nebula, my first target. Unfortunately, I forget about
the rotating tube of the Questar, and the camera and lens pull the barrel
over on its side and wedge themselves against the fork arm. Barrel tension is
adjustable, but the nearest known screwdriver of appropriate size is 279 miles
to the south. While my companions are viewing various deep sky objects through
binoculars and an 8" Dobsonian and having the time of their lives, I mutter
several unimaginative oaths and replace the large lens with a simple 50mm lens.
It, too, gradually pulls the scope over on its side, apparently due to the
weight of the old Canon F-1 camera body. I give up and lend the Questar to
a companion and experienced astrophotographer, who gets several photos with
a lightweight Olympus camera body and a 50mm lens.
Chagrinned, I wander over to the AAI encampment to look through a large Dob.
One of my main reasons for coming to Stellafane is to look through some large,
high quality telescopes. In the past I have heard many excuses from owners of
large telescopes as to why their instruments have such poor resolution. I have
been invariably disappointed by their telescopes, preferring the razor sharp
resolution of the Questar (in spite of its small light grasp) and my 6"
Newtonian. But I recently ordered a 15" Dobsonian of my own, one with "the
best optics available" and claiming diffraction limited performance at full
aperture. Did I buy into hype? Is it really impossible to get excellent
performance from a large telescope? I had to find out.
The Dobsonian is a home made 17.5" job with a solid tube. I climb the ladder
and peer into the eyepiece at a "blinking planetary", NGC somethingorother. I
focus. Hmmm. Stars are pinpoints at the center, and not too bad at the edge.
I ask the magnification. Over 200X. I ask about the mirror. Full thickness,
club ground. I ask about the mount. Three point. I ask about collimation.
Approximate. I am happy. It can be done. Tomorrow I will go to the telescope
field and seek out the ultimate.
DAY TWO:
The day is off to a bad start. We had time warped to our rooms the night
before, arriving an hour and a half earlier than the time on the clock in
the van. Now we awoke at different times and headed off in search of
separate breakfasts in spite of our previous agreement to meet. I walk to
the HoJo's with the astrophotographer, and we arrive simultaneously with a
busload of non-English-speaking tourists all looking for takeout meals.
After five minutes of non-service we leave. I grab a coffee and some fruit
pies from a nearby truck stop, and we head off to Stellafane late. We miss
the swap tables, which had closed hours earlier. We head for the amphitheater
in search of the afternoon tent talks, only to find it deserted. We conclude
that we were mistaken and that there weren't any tent talks. Little did we
suspect they were being held in the tent.
We wander over to the telescope field on Breezy Hill to see what's there. I
am surprised to see relatively few telescopes, and little that is really unique.
There is a trischiefspiegler, and a wooden refractor. The "Star Car" -
binoculars built for two in a driven chair - are a big hit. There is an
unassuming red Dobsonian. A newly designed f/13 refractor objective made from
a new glass is installed in a 6" Astro-Physics tube and mounting. In the far
part of the field are several small refractors with H-alpha filters giving
sharp views of the sun. More Dobsonians, including a 30", and the Obsession
2 - a 25" f/5 I am determined to see. The famous Porter Turret Telescope
oversees it all.
One of the advantages of an event like Stellafane is being able to see in
the metal telescopes we only read about in the magazines and spec sheets.
It is one thing to dream about owning a big refractor, but quite another
to greet it face to face and discover it is far bigger than you are and
will not go gently into that dark night. Similarly with the Obsession 25":
a surperb machine, but huge beyond the ability of measurements to convey.
These suckers are big. Even if you could afford them, could you use them?
I scan name tags, looking for ASTROFORUM members, finally recognizing one
by picture and confirming by badge: David Levy, comet hunter. I introduce
myself, and we chat for about a minute before old friends discover him and
I am dragged away for yet another group photo opportunity. But I do get
some advice for my 1991 trip to see my first total solar eclipse: Leave
the cameras at home. Just lay back and enjoy it. After the previous night's
fiasco, it is advice I am happy to receive.
We walk back to the van. The afternoon is humid and hot. We dare not leave
and lose our parking spot, but there is nothing left to do, and it is hot.
We pile in and run the air conditioner, ozone hole or no. It's hot. Other
members arrive. Beer appears. Smoke accumulates. I sit outside in the shade
of the vehicle as the sun descends and the heat dissipates. We go off to
the food tent to secure some dinner, then I walk around examining the
telescopes in the various parking fields. There are commercial SCT's, home
made equatorial Newtonians and Dobsonians of all sizes, and refractors here
and there. A tiny 4.5" Serrurier truss tube Dobsonian catches my eye - I
recommend a teeny Telrad. Everyone is in a social group, not excluding
visitors, but not quite inviting them either. Perhaps by nature we are
all shy people.
Sunset arrives, and we gather again in the amphitheater. I spot a star
cluster in the gathering dusk: J. Kelley Beatty, Roger Sinnot, David Levy,
and Stephen J. O'Meara, with an outlying Al Nagler, and Dennis diCicco
faintly suspected. Prizes for the mechanical and telescope design
competitions are announced. Raffle tickets are drawn for various door
prizes, including a set of Nagler eyepieces in a case. First time
Stellafaners are welcomed. And we finally find out what a "fane" is.
Walter Scott Houston is away in Europe at an AAVSO meeting, so I miss my
chance to hear this legend give his "Shadowgram" talk. Instead, there is
a representative of the Department of the Interior who presents the
Springfield club with a plaque declaring the Stellafane clubhouse and
Porter Turret Telescope as national landmarks. Then a representative from
NASA courageously appears to give the assembled telescope makers an update
on the defects in the Hubble Space Telescope, which was apparently placed
into orbit with insufficient testing and 1/2 wave of spherical aberration.
The keynote speech and highlight of the evening's program is a talk by
David Levy. He told us about comet hunting; not so much how, though there
was some of that. Mainly, he told us why. He spoke of his enthusiasm,
and of the romance of the night, and of being the first person to see a new
visitor to the inner solar system. A song called "The Lady in Red" played
as he showed slides of Comet Halley taken in red light, and it summed up his
feelings so well.
Then it was over. We walked back to the van under bright hazy skies, and many
people drove away to their hotels. But the best was yet to come. I left my
companions to sleep in the van and joined two members of my club travelling
independently, and we headed for Breezy Hill to see what the creame of
telescopes had to offer.
The field seems larger by night. The walk is longer. Haze and occasional
clouds are lit by light pollution in the north. Deep sky observing is out
tonight, but haze brings good planetary viewing, and Saturn is high in the
south. We head for the Obsession 2, but it is closed down. An announcement
over the loudspeaker reminds us to use only red lights. "Yeah, what about
that aurora?" someone quips. Aurora? We look. Just light pollution. Quite
a *lot*, it seems, but just that. We move over to the Porter Turret Telescope,
but that, too, is inoperative, still being assembled. The light pollution to
the north gets worse. We move to the trischiefspiegler and get on line to
view Epsilon Lyrae. The light pollution to the north breaks into rays and
begins to pulse. We have aurorae!
As the line for the trischiefspiegler moves, the crowd notices the growing
aurora. Oohs and ahs are heard. The trischiefspiegler shows Epsilon Lyrae
clearly resolved into four components, but with some astigmatism. Not as
sharp as I had expected. We moved on.
A line was forming for the Turret Telescope, so my two companions get on it.
I check out an 8" SCT standing nearby and pointed at Saturn. Whoa! This is
sharp! What kind is it? "Bausch & Lomb." Did you do anything special to it?
"I cleaned some debris off the mirror, that's all." Did you collimate it?
"Not really." What kind of eyepieces? "Clave'." Hmmm. Very interesting. Only
the second SCT I have ever seen with a pleasing, sharp image, but an
exception that breaks the rule. Applause break out as the aurora pulses
to the zenith and sends out vertical rays. It is faintly green, though
one observer claims to see a yellow layer.
I get on line for the Turret Telescope and continue to watch the aurora. I
read somewhere that the Turret scope produces cruddy images. Once inside,
I find the image of M13 sharp and steady, with no trace of softness or
any movement of the image. I am impressed.
Outside, the aurora continues to build, with large scale flickering and bright
regions appearing and vanishing. My two companions head back to the van to get
their cameras and tripods to photograph the aurora. I stay, stumbling slowly
over the unfamiliar ground and still unsteady in the darkness. People are
lounging on the hillside below the Turret looking up at the sky as the aurora
climaxes. It now covers the entire sky, and the north is a laser show. I hear
a fellow on the slope above me hug his sweetheart and say "Thank you. Thank
you very very much. This is so wonderful." And it is.
The aurora subsides. I decide to explore some more, and head toward the
Obsession 2 in the far part of the field. It is now operational, and there is
a long line. I join the line, and watch the aurora, which has picked up again.
Half an hour or more later, I approach the telescope, which is now pointed
at M27. This will tell me once and for all whether a telescope of this size
can perform. As I get closer to the scope, the automobile a few feet away
begins to stir with alarm chirps and flashes of light. I am at the foot of
the ladder. The car springs to life, engine and parking lights on. My dark
adaptation draining away, I climb the ladder while shielding my face. The
car leaves and I look into the eyepiece.
M27 is bright, with the classical "dumbell" shape rounded out by less bright
bulges of nebula. Stars are sharp pinpoints all over the field, to the best
of my ability to see them. The scope is performing far beyond the abilities
of the similar sized instrument at the NJAA observatory, proving to my
satisfaction that the latter scope is in need of serious rework. I am also
relieved, since the firm that made the primary for the Obsession 2 is making
the one in my future telescope. It should be good.
I am excited yet tired, so I move on. Most of the crowd is gone, and it is
easy to look through almost any telescope. I check two large refractors.
Nice, but a bit soft, probably due to dewing and some haze. Seeing is rock
steady, however. I head back toward the Turret in search of my lost companions.
I come to the unassuming red Dobsonian I noticed earlier in the day. It is
pointed at Saturn, and is so low to the ground that I can reach the eyepiece
while sitting comfortably on the hillside. I center Saturn in the finder and
look into the eyepiece. "OOOOH!" "OOOOOOOOOH!!!" THIS IS THE SHARPEST VIEW OF
SATURN I HAVE EVER SEEN! I check the eyepiece with my red flashlight. It's
a 12mm EDSCORP Kellner! The owner comes to check me out. What size is this?
"12.5 inches, f/6." Who made the mirror? "I did." What kind of surface accuracy?
"It works out to 1/32 wave, but I don't think it's that good." What kind of
mounting? "Three point." Did you collimate it? "Yeah, in my living room."
It is incredible. I can see the C ring all around, (I had never seen it
before, except in projection against the globe.) and details in the cloud
bands on the globe. The Cassini Division and the shadow of the globe on the
rings are no problem. The image is razor sharp, and there are several moons.
I call over my companions and insist they look. "My *word*!" "Wow!" We keep
coming back again and again. Minutes later, the loudspeaker announces the
winners of the optical quality awards. This scope ties for first place. I
disagree. It has no competition, anywhere on the field. With the announcement,
a line quickly forms. I move on.
I am sated, but I check out a few more scopes. The wooden refractor shows
promise, but its high power eyepiece has been stolen, and it is now limited
to about 30X. A Maksutov Newtonian is OK, and a commercial Dob is blurry,
but so are my eyes. I return to the little red Dob to see Mars, but it's
too low and I can't focus anymore. One of my companions also wants to leave
and agrees to guide me to my van. The rest of my group is waiting, and we
return to our motel. It's over.
LESSONS:
Stellafane taught me that almost any kind of telescope can perform well. I
don't know what the secret is, because they all use different designs, mounts,
eyepieces, apertures and degrees of collimation. Perhaps the key is a user
determined to get the most from the equipment and settle for nothing less.
But I do know that it can be done, and there really is no excuse for poor
full aperture performance from any type of scope.
Stellafane also taught me that sometimes the best equipment to bring with you
is no equipment at all. It's a lesson I'll think about often as I prepare for
the 1991 solar eclipse.
All in all, I had a great time, and I hope to be back next year, with more
wisdom and a lot less luggage.
Larry Geary
74017,3065
August 2, 1990