By Tim Hunter and Dan Knauss
Messier Marathons have become popular in the last 10-15 years.
Near the time of the spring equinox it is possible for an
experienced observer to view all the Messier objects in one
night. We wondered for some time how many Messier objects could
be photographed in one evening with one telescope. Accordingly,
we set out to do a photographic Messier Marathon.
Our rules were simple. To count as a genuine photograph of a
Messier object, images on standard 3.5 x 5-inch prints or on
contact prints of the negative sheet had to be easily
recognizable as being the Messier object claimed when compared
to the photographs in the Messier Album by Mallas
and Kreimer.
In early March 1988, two weeks before attempting the
photographic marathon, we initiated a thorough review of the
objects and their locations, studying star charts, pictures, and
written descriptions of them. A field notebook was prepared
containing a list of all the Messier objects, their size, type,
and estimated magnitude, as well as their coordinates (2000).
The list was arranged in object viewing order using a sequence
originally suggested by Wally Brown of Phoenix. A list of 20
bright stars (Sirius, Riegel, et cetera) and their coordinates
was also drawn up to be used for periodic calibration of our
telescope's setting circles throughout the night. This
effort took place in 1988 prior to computerized star atlases and
digital setting circles.
EQUIPMENT & TECHNIQUES
The 24-inch f/5 Newtonian reflector at the Grasslands Observatory in
Southeastern Arizona was used for the marathon. The observatory
is located at a superb 5000 foot altitude dark-sky site. The
pictures were taken through an Olympus OM1 camera at the
telescope’s Newtonian focus. Because the telescope is well
aligned and has an excellent drive, no guiding was done. The
camera’s horizontal axis was generally aligned in the east-west
direction, and the camera was critically focused with a
magnifier each time we changed a roll of film. For all the
exposures, we used hypersensitized Konica SR-V 3200 film. The
objects were initially found either by visual sighting through
the telescope’s five-inch f/5 refractor finder, or by using the
telescope’s large setting circles. The setting circles were
especially needed for speed and accuracy when acquiring objects
in the Virgo and Coma Berenices regions. Mallas and Kreimer’s
book proved invaluable and was frequently consulted during the
night’s efforts. The exposure times ran from one minute for
bright open clusters to two minutes for globular clusters and 3
minutes for galaxies, nebulae, and planetaries.
It was a two-man operation all the way. One person would find
the object in the finder or align the setting circles and keep a
log of the time, object, exposure number, and exposure length.
The other person would climb the fourteen foot viewing ladder,
use the telescope to acquire the object in the camera’s field of
view, and take the exposure. We frequently traded off jobs
during the night.
THE TRIAL RUN
In astrophotography nothing ever goes right the first time.
Knowing this, we had trial run on the night of Friday March 18,
1988 to practice our techniques and to get the bugs out of the
system. It was most fortunate we did this, because we committed
a whole series of blunders, some of which would have doomed us
on an actual marathon night. We first forgot to take the covers
off the telescope mirrors. Then we had trouble rolling the roof
off and forgot to turn on the clock drive. We, of course, also
took a few exposures at 1/30th second rather than on the bulb
setting. Our most serious error was that which is feared by all
photographers; the film was not put on the spool well enough and
did not wind through the camera. Thus, we spent 3 hours taking
21 test shots before we discovered this error. We had to spend
another 1-1/2 hours taking new test pictures. These were exposed
on regular Konica SR-V 3200 film and developed the next morning
so we could gauge the exposure range necessary for the marathon
attempt. In calibrating our exposures for the marathon effort,
we assumed that the hypersensitized SR-V 3200 would be twice as
fast as the regular Konica SR-V 3200 film.
THE PHOTOGRAPHIC MARATHON
The marathon was performed on the night of Saturday/Sunday,
March 19-20, 1988. We arrived at the observatory 2 hours before
sunset and got organized with plenty of time to go before sky
darkening took place. We brought along a backup camera, film,
and a Porta Pac rechargeable battery in case the observatory’s
generator failed. We were also dressed very warmly, because the
average temperature for the evening was 32° F with no warming
facility available other than the car.
The marathon was very successful with photography starting
one-half hour after sunset and proceeding until fifteen minutes
before sunrise. 96 frames on four rolls of film were exposed.
103 total objects can be identified on contact prints of the
negatives. 84 of them are Messier objects, and 19 are assorted
NGC or IC objects. One hundred of the total objects were
photographed with the 24-inch telescope. The Pleiades (M45) and
the Orion Nebula region (M42/43) were taken through the
five-inch f/5 finder telescope which afforded us a large enough
field of view for these objects. Twelve of the frames were
ruined by wind and other problems. Vigorous wind gusts made
telescope tracking impossible and shut us down for two hours
from 10:30pm to 12:30am. We averaged about 12 objects per hour
and could conceivably have photographed nearly 100 Messier
objects if the wind had not interfered. To view our images go to
the Photographic Messier
Marathon Album.
The four rolls of film were developed by a Fast 1-hour Foto
Store with excellent results. The rolls were run through the
processor with the same setting used for Konica 400 film. Even
though our intention was not to produce beautiful pictures, but
merely to get as many recognizable images as possible, we did
obtain a surprisingly fair number of nice photographs. Many of
the pictures were somewhat marred by large streaks of static
electricity discharge, a problem we had previously not
encountered. The relative humidity at the observatory was only
4% along with considerable wind and dust. Static electricity was
very evident about the observatory and the telescope. Every
attempt was made to handle the film carefully and not wind or
rewind it rapidly. Nevertheless, static discharge was a problem
and might conceivably be a particular nuisance with
hypersensitized film used under very dry conditions. We
recommend careful film handling with slow film rewinding.
Grounding the telescope and the camera might also be helpful
under these types of conditions.
CONCLUSIONS
It is possible to photograph the vast majority of the Messier
objects in one night. It is probably not possible to photograph
them all, because some of the very early evening and early
morning objects will be low on the horizon and burned out by
twilight. They are difficult enough to see even with a large
telescope, let alone photograph well. It is probably possible to
obtain pictures of 100 of the Messier objects in an evening if
you plan well, have luck, good equipment, and superb viewing
conditions. If you like astrophotography and want a challenge,
give it a try. A photographic Messier Marathon is mainly done
for the fun of it, but it does have an added benefit. You now
have a consecutive series of pictures of the Messier objects all
taken with the same equipment and film and with the same
observing conditions, if you discount photographs of those
objects low in the sky. It is now possible to do rapid side by
side comparisons of the objects' relative size, brightness, and
color. This is something that is not yet available from any book
or published picture set.
Essay originally posted December 1998 (prior to modern digital imaging and digital telescope systems)
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