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Why I No Longer Use Film - or why I switched to the digital world
By Tim Hunter
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Introduction – Astrophotography versus Common Sense
Astrophotography defies common sense. For much less money and
effort, you can enjoy better results in books, popular
magazines, and on the web. However, many years ago I crossed
that bridge, and there is no going back. Astrophotography is
challenging. It requires time, effort, and considerable luck to
produce a good picture. Therefore, I would never criticize the
work of another. I enjoy any effort to capture the splendor of
the night sky. There is beauty in every picture of the Heavens
no matter how ineptly it was taken:
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Prime focus image of M20(?) with Ektachrome
400 film and a Celestron C-8 telescope. Ten minute exposure. T.
Hunter circa 1983.
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The Past
I have been an amateur astronomer since 1950, and
astrophotography has undergone a revolution since the 1950’s and
1960’s when I grew up. In those days, most photography and all
astrophotography was with black and white film. Color
astrophotography did not exist.
One of my astrophotography heroes was Dr. Clarence Custer* whose
superb black & white images graced many a page and centerfold in
Sky & Telescope. One of his all time best images is the montage
of the Great Andromeda Galaxy (M31) published as a centerfold in
Sky & Telescope in May 1958 (Custer, 1958):
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| Scanning and reproduction of Dr. Custer’s image in this essay
can not do the original publication justice. He used
the prime focus of a homemade 12 ½ -inch Newtonian telescope to
compose this montage, which consists of three 90-minute
exposures on Eastman 103a-o plates. Extensive darkroom
manipulation was performed to hide the montage lines. Walter
Baade estimated the limiting magnitude of this set of images as
17.5. Modern CCD cameras and commercial telescopes available to
the amateur astronomer can easily exceed this magnitude limit
with very short exposures (Hunter, 2004): |
M67. 60-second exposure with an Apogee KX260
CCD camera at the prime focus of a Meade LX 200-12-inch
telescope. The limiting magnitude is approximately 18. T. Hunter
In my opinion, black & white astrophotography reached its peak
with the publication of Mallas and Kreimer’s classic work The
Messier Album (Mallas and Kreimer, 1978). The pictures of the
Messier Objects by Kreimer are the standard for which even
modern CCD imaging has a hard time meeting.
Kreimer’s pictures were lengthy exposures taken with painstaking
effort, and their printing involved extensive darkroom work. He
used Kodak Tri-X film with an ISO speed of 400.
I first tried astrophotography in the late 1950’s, and the
results were terrible. I could not build or purchase a telescope
with a good enough drive to track on the sky for long exposures
through the telescope at its main focal point (prime focus). My
first successful ventures included a picture of the Echo I
satellite in 1962 and an aurora picture published in Sky &
Telescope in 1961 (Hunter, 1961):
Echo I Satellite, July 21, 1962, 11:50 EST pm. Kodak Tri-X
film, 5-minute exposure with a Brownie Hawkeye Camera (45 mm f/2.8). T. Hunter
Aurora, 1961. T.Hunter
These and other subsequent successful images involved time
exposures with a cheap 35mm camera mounted on a tripod. I used
the fastest film available at that time, Kodak Tri-X, roughly
equivalent to an ISO speed of 400 by today’s standards. I also
used the built in camera lens (focal length ~ 50 mm).
Successful professional color astrophotography did not take
place until 1959 when Super Anscochrome was introduced (Miller
1959; Carpenter 1959) . The first amateur color astrophotography
pictures were published in Sky & Telescope in 1963 and 1964:
Cover of Sky & Telescope August 1963.
Cover of Sky & Telescope December 1964
I was quite fortunate to meet Dr. Custer in 1986, and he
was kind enough to give me an original print of his montage
which I framed and now proudly display in my den.
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