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Jon-
Well done, doesn't look like too many mistakes to
me. They are all good, the Lagoon/Trifid is very nice. Looks
like you had another good "adventure in astrophotography", looking forward to
your star trails shots. Thanks.
----- Original Message -----
Sent: Saturday, May 05, 2001 8:05
PM
Subject: [APML] Chiricahua Adventure and
New Images
As some of you know, I recently drove down to Chiricahua
National Monument
in Arizona. Out of three nights I was there, two
were suitable for
astrophotography, the first night being lost to high
winds (my portable
annemometer said the peak was 48mph!) and high
clouds. The second night was
clear and calm, but the black parts of
the sky did not appear to be as black
as I'm used to in Colorado. The
third night was clear, but windy, and
exhibited the same relatively low
contrast compared to what I'm used to. I
suspect that there was a lot
of dust thrown into the sky by the high winds
during the day that I arrived
(these mountains are basically and island
surrounded by desert), or
possibly high water vapor content in the
atmosphere. My portable
instrument showed humidity of around 45% early in
the second night, then
climbed to 75% by about local midnight, and dew
started forming on some of
my cases. Then, within two hours the humidity
had dropped to 25% and
the dew evaporated. The third night was dry all
night at around 20%,
but as I said windy with some gusts of around 20mph.
The seeing on this
last night was very shaky down where all the good stuff
was.
The
site I chose was Massai Point, since the southern horizon is somewhat
lower
and less obstructed than the Echo Park trailhead parking lot.
Conditions at
both of these sites are decadent by my standards, with paved
areas to set
up, restrooms, and even bear-proof trash cans for those
film
wrappers. Despite the altitude of nearly 6900 feet, the
temperature never
dropped below 40 F - balmy by any nighttime standard I'm
used to.
The good news is that I got to meet up with list member
Dean Ketelsen and
his friend Roger (insert hard to remember or spell name
here). They both
brought along their self-built scopes. Dean's was a
large, fast Newt (11"
f/3.5 with coma corrector) with a cleverly integrated
Newt guidescope all in
one unit. Roger's was an imposing folded
8" achromatic refractor. We
were, as Dean said, "all G-11 men" that
night. This is the first time I had
ever done deep sky work with
other telescopes and astrophotographers
present, and so it was a new
experience for me. The view through Roger's
refractor of Omega
Centauri is one that will take a severe head injury to
forget! Dean
pointed out the zodiacal light to me - something I had never
recognized
before. Many thanks to Dean and Roger for making the long drive
out
from Tucson to join me. The conversation and comeraderie were
most
appreciated, as were the views.
The bad news is that I made
tons of mistakes. I must have kicked the tripod
the first night of
imaging, since all the shots have field rotation, even
after a lengthy
drift alignment. The second night I failed to tighten
clutches down
on all of the shots, such that the wind caused some trailing
in several
images. And, nearly all of the medium format shots with the
Borg
100ED were blown due to poor focus. To add insult to injury, the
images
with the very best focus, guiding, and alignment were attempts at
very faint
stuff that I have not seen imaged before (although I'm sure they
have been
by somebody) like IC4601, Zeta Ophiuchus, and Sh2-1. These
atttempts were
promising, but not quite enough for my processing
skills.
However, all was not entirely lost, as a handful of 35mm images
are decent
enough to post at web resolution while I scheme a reshoot
strategy. They
were all taken with the Epsilon-160, and can be found
as "New Images" here:
http://home.datawest.net/jkolb/astrograph.htm
The
star trails, scenics, and a couple of the successful wide-field 6x7
shots
are still in progress. I also have updated my Dark Sites page,
if
anyone's interested, with a map from the Color Landform Atlas of the
United
States. The new page layout can be viewed here:
http://home.datawest.net/jkolb/dark_sites.htm
Comments
and questions are welcome. And Dean, you were right, the
restaurant
at the truck stop in Willcox wasn't half bad.
Sincerely,
Jon
Kolb
Adventures in Astrophotography
http://home.datawest.net/jkolb/
jkolb@noochee.com
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