plates of earlier times. In 1876 the first spectrum of
Vega was completed by a spectroscopist, W. Hug-
gins, who also did the first spiral galaxy in 1899.
Photography dramatically changed in 1884 when
George Eastman once again advanced the art with
the invention of the celluloid-based photographic
film. But astrophotographers continued to use the
glass plates for several reasons, such as film can
shrink and warp over time, film is not completely
flat all the time, and telescopes at observatories had
large focal planes and had no use for the smaller film
image frames. However for the backyard astropho-
tographer and the traveling scientist, the use of
Kodak’s new roll film was ideal.
Color and CCD
Astrophotography continued to be shot in black
and white although the Kodachrome process was
marketed in 1935 and color film had been intro-
duced commercially during the 1940s. There was a
problem in trying to capture a color image of the
heavens because long exposure times resulted in
distorted color representation. The sensitivity of
the film needed to be increased so the exposure
time could be shorter. The Kodak 103a spectro-
scopic films were still more sensitive than the color
film and also the color films were not available in
plate form. William Miller of the Mount Wilson
and Palomar Observatories was the pioneer of
color astrophotogrpahy. The 200-inch Hale reflec-
tor telescope at Palomar Observatory was built
exclusively for photography. In 1959 Miller used
Super Ansochrome, a commercially available
reversal type film. Miller gave the film extended
exposure time to offset the problem of reciprocity
failure due to the film’s speed, ASA 100.
Eastman-Kodak solved the problem of low-
intensity reciprocity failure. This is where the
photosensitive grains of the emulsion do not
respond to light in a linear way because water and
oxygen molecules become trapped within the emul-
sion. The answer was hypersensitizing, also known
as gas hypering.
In 1969, bubble memory, a new type of computer
memory discovered at Bell Labs was made sensitive
to light. More sensitive than film, they are stable
and can be directly input into a computer. Emul-
sion based astrophotography was replaced by the
introduction of charge-coupled device or CCD sen-
sor. The CCD is a small chip broken up into very
small cells. Light traveling through the lens, is
reflected by mirrors, then reflected by a prism
onto the surface of the CCD detector. CCD is af-
fected by the photons of light when hit. Photons
hitting the surface of the CCD knock electrons out
of place in the cell. While CCDs were becoming
popular, Kodak introduced a new film, Tech Pan
in 1980, an emulsion with high contrast and sensi-
tivity that also recorded infared and ultraviolet
objects. CCD however, had become the preferred
method for astronomy. Most professional observa-
tories now use the CCDs. CCDs were also the
choice of NASA for the Mars Pathfinder mission,
which upon landing on the Martian surface on July
4, 1997, began to send back very sharp images of
the red planet.The Camera in Space
Astrophotography in the twentieth century lit-
erally reached new heights. Now the cameras
themselves were actually flying through the very
heavens they had earlier captured while attached
to telescopes on terra firma. In 1959 the Soviet
Luna 3probe swung around the moon and cap-
tured the first photograph of the moon’s far side.
Sister probe toMariner 3,Mariner 4reached Mars
in 1965, and took the first close-up images of the
Martian surface. NASA’s Apollo missions had the
objective of using photography to map the entire
lunar surface. Hasselblad cameras were used with
both black and white and color film. Several cam-
eras were mounted within the command module
while several other that were controlled by the
command module were stowed in the scientific
instrument module. The voyager space probes dur-
ing the period of 1979–1980 sent back photo-
graphs of the planetary family as they swung by
Jupiter and Saturn. The most astonishing photo-
graphs of the universe were to come once again
from a telescope, but this time the telescope was
floating in space. Launched on April 4, 1990 at
12:33:51 UTC, the Hubble Space Telescope began
to send back remarkable images of our own galaxy
as well as others. A 2.4 m, f/24 Ritchey-Chretien
telescope, the Hubble could make observations in
visible, near-ultraviolet and new-infared. The ima-
ging and spectroscope of the future is the Next
Generation Space Telescope, whose primary mir-
ror diameter is twice that of Hubble’s and
designed to see the far visible to the mid-infared
part of the spectrum.Camera and Tripod
The most accessible type of astrophotography is
that of the camera mounted on a tripod. The cam-ASTROPHOTOGRAPHY