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If
you do much historical research, one of the things you're going
to run across is beautiful, highly-detailed panoramic drawings done
in the 17th, 18th, and the first half of the 19th Centuries. Many
of these drawings were done by the United States Army Corps of Topographical
Engineers- the Army's mapmakers. In a recently-published book on
Western Texas, several of these panoramic drawings were included.
The text stated that the technique for making such drawings is 'lost,'
and "no one today knows how the perspective was achieved."
The technique, which is very old--Leonardo da Vinci used it, as
did most of the 'old masters' who painted landscapes--hasn't been
lost. It's just been replaced, and most artists would be glad it's
no longer used. The technique required a very cumbersome piece of
equipment and, except in the dead of winter, the heat involved was
terrific. Still, the technique is well-documented. It's called camera
obscura.
Almost as soon as the first explorers began to move into the west,
artists followed. Many of these artists were Army Topographical
Engineers. Their job was not to 'interpret' the scenery, but to
render, as precisely as they could, exactly what they saw. These
were terrain drawings, and they had to be as exact and detailed
as possible, with proper perspective. Looking at these drawings
is almost like looking at photographs-and that, almost, is what
they are.
If you were a Boy Scout back in the '50s and tried for the Photography
merit badge, one of the things you had to make to get the badge
was a pinhole camera. A pinhole camera is the simplest camera there
is-a camera without a lens. To make mine, I found, in a second-hand
store, an old Kodak box camera that used the now-discontinued 616
film. I removed the lens and shutter mechanism and replaced the
lens with a thin piece of sheet brass in which I made a very tiny
hole. The merit badge manual recommended the hole be .075" or 75/1000
of an inch in diameter, but I didn't have anything to measure it
with, so I poked a dimple in it with the point of a dissecting needle
and a tackhammer and then filed the dimple off. I covered the hole
with a piece of electrician's tape. I loaded the camera, and when
I was ready to take a picture I simply removed the tape. A little
experimentation gave me the proper exposure time.
I had, in effect, made a miniature camera obscura. The word
camera actually means 'room' in Latin and obscura
means 'dark.' That's exactly what the Topographical Engineers toted
all over the west in the 1830s, '40s, and '50s. It was a portable
dark room-not a 'darkroom' as in photography, but a dark room that
could be disassembled, loaded on wagons, taken to the point at which
the drawing was to be made, and then assembled for use. This 'dark
room' was a light-tight box about eight feet on a side. In the exact
center of one wall there was a small hole, usually equipped with
an iris that could be opened and shut from the inside.
The artist set up his box with the hole in the side pointing toward
whatever he was supposed to draw. He put, on the back wall, a very
large piece of drawing paper-about 6'x6'. If it was at all hot he
stripped to his underwear or even to the altogether, climbed into
the box, and his assistants shut the back to seal out all light
except that coming through the tiny hole. The light coming through
that hole projected, on the paper on the back wall, an inverted
image of the scene outside.
After considerable yelling through the lens-hole and shifting the
box, the artist got the scene he wanted on his paper. Then, with
charcoal sticks or pencils or whatever, he blocked in the major
outlines of the scene. That done, he banged on the box to be let
out, probably collapsed on the ground as soon as he got out, slugged
down about a gallon of water, and then rolled up his paper.
Once he had
the paper back in the studio he transferred the huge image, which
was just outlines, to a smaller, more manageable piece of paper-or
canvas, if this was to be a painting and not a terrain drawing-by
means of an artist's pantograph. When the transfer was complete
the artist added shading and detailing, and a wonderfully accurate,
seemingly impossible drawing or painting emerged.
The
technique was in use by artists and engineers for nearly 500 years,
but in 1837 a Frenchman named Louis DaGuerre began to make it obsolete.
DaGuerre invented the first practical photographic process that
year and began to go public with it in 1839. At first this new 'art
form' was used mainly in studios, with only an occasional foray
into the outdoors. The emulsions DaGuerre used were very insensitive.
Modern photographers consider a film with an ASA or ISO speed of
25 to be a very 'slow' film. DaGuerre's 'film speed' was probably
around ASA/ISO .0005. It took an exposure of as much as a minute
and a half to take a portrait in a brightly-lighted studio in 1840.
By 1847 photography was sufficiently advanced that a photographer
traveling with General Winfield Scott's Army in Mexico City photographed
Scott and his officers in front of several landmarks in the city.
In 1848 Mary Maverick, in her diary, mentioned having her photograph
taken in San Antonio.
By 1860 photography had advanced sufficiently that a huge camera
with a very long focal length, using a very large sheet of sensitized
glass or metal, could be transported by wagon fairly easily. Suddenly
there was no further use for the camera obscura and the pantograph.
An artist or engineer could capture, in only a few seconds, on the
photographic plate, in much more precise detail, what his predecessor
had labored for hours to capture on the paper on the back wall of
the sweatbox.
The camera obscura produced some of the finest art and engineering
drawings in the world. It was an invaluable tool, not merely for
the artists for whom it was designed, but for soldiers, cartographers,
and military engineers the world over. It's very doubtful, though,
that any of them lamented the demise of the old sweatbox when photography
replaced it.
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