All the photographs
brought back from the moon are correctly exposed, correctly framed,
and crisply in focus. This seems suspicious. [Ralph Rene]
It would be suspicious if it were true. As a matter of fact, a
significant percentage of the lunar surface photographs are blurred,
unfocused, incorrectly exposed, or otherwise flawed. These photos
weren't available to the public until recently because they weren't
interesting to the public and therefore not cost-effective to
duplicate. But now that it's possible to efficiently digitize the
many thousands of photographs taken on the moon (even the bad ones)
and distribute them cheaply via the Internet, we can see the full
gamut of lunar surface photography.
Below are a few unintentional photos that appear on the Apollo
film rolls. These typically occur at the beginning of a new roll
when the astronaut has to advance a few frames to get to fresh film.
They're usually out of focus and badly exposed.
NASA: AS17-134-20376
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NASA: AS17-138-21028
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NASA: AS17-140-21351
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Many photographs contain lens flares
because they are up-sun segments of
pans used to document the surroundings of important events in the
checklist. These photos are important to the scientists studying the
returned samples, but are not usually interesting to the general
public. The scientists use them as documentation and ignore any
aesthetic flaws they may see.
Below are two photographs in which light has leaked into the
magazine. This sometimes happens to the last picture on the roll when
the astronaut removes the film magazine from the camera, especially if
the photographer has not wound the film fully into the magazine.
These images are said to be "sunstruck". In the first image a streak
of white completely obliterates the left side. In the second image
the upper left corner has been given an orange tint, but the details
are still visible.
NASA: AS16-112-18273
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NASA: AS16-113-18380
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The rest of the images below are flawed in some way. Some have
lens flares or are poorly focused or strangely framed. While they are
still valuable, they are not perfect. The point is not to argue that
the astronauts were poor photographers, but that the photo record
indeed shows that the photographs were taken in an uncontrolled
environment with a high proportion of imperfection.
NASA: AS12-46-6715
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NASA: AS15-82-11201
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NASA: AS12-46-6738
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NASA: AS16-105-17220
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The Hasselblad cameras
didn't have viewfinders, automatic exposure, or automatic focus. How
were the astronauts able to get any good photographs at
all?
Believe it or not, people were able to take good photographs
before automatic exposure computers and automatic focus devices were
invented. It required a bit of training and practice. Film
manufacturers commonly provide exposure guides giving the average
correct camera settings for common lighting conditions.
The lack of viewfinder was occasionally a problem. Early missions
used a wide-angle lense. It was sufficient to point the camera in the
general direction of the subject and you would be likely to frame it
well enough. On later missions a 500mm telephoto lens was also taken,
and the cameras were modified with sighting rings to help aim them.
Normally the camera would be mounted on the space suit chest bracket,
but for telephoto use the astronaut would have to remove it and hold
it at eye level in order to sight down the rings.
Manual focus is not as problematic as many suppose. Lens
manufacturers mark the expected distance to the subject on the focus
ring, and it's simply a matter of measuring or estimating the distance
from the lens to the subject and setting the ring for that value. To
aid the astronauts in measuring the distance to subject, length of
commonly used tools was marked on the lens. Several Apollo
photographs show the tongs and scoops used as distance references.
Focus need not be exact either. Because of photographic depth of
field, it's possible to set the focus distance inaccurately and still
have a sharp photograph.
The exposures were worked out ahead of time based on
experimentation. The ASA/ISO rating of the film was known, and NASA
photographers precomputed the necessary exposures. These figures were
refined over the course of the program. In many cases the camera
settings for planned photos were given in the astronauts' cuff
checklists. In other cases the astronauts followed some basic rules.
Shutter speeds were typically 1/125 or 1/250 second. F-stop
settings varied from f/5.6 for up-sun
photos to f/8 and f/11 for cross-sun and down-sun photos. The predetermined
exposures probably erred on the side of overexposure. It's easier for
a film lab to correct for overexposure than for underexposure.
Automatic exposure controls were available on several consumer
camera models during the late 1960s. Apollo 11 Command Module Pilot
Michael Collins suggested that Hasselblad look into the possibility of
incorporating this technology into the camera after his experience on
Apollo 11. Apparently the professional photographers who used the
Hasselblad model upon which the lunar surface cameras were based did
not want automatic exposure controls on their cameras and so it was
not a standard feature.
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