The Ely miner. [volume] (Ely, Minn.) 1895-1986, 1931-08-21

lance aer1al Photography laQ Deen
set by the air corps OF the army when Capt. A.
W. Stevens, Photographic expert, succeeded in
taking a picture covering a distance of go
miles in single exposure. In 1929 Captain
Stevens had set long distance Photographic
record when his camera registered objects 227
miles away from the camera eye but his 1880
fight in a plane piloted by Lieut.. John D.
Cerkille over Crater lake in Oregon added more
than 80 miles to that record.
Upon his return from this flight, Captain
Stevens declared while am very well salts
fed with the results obtained this particular
mission, am inclined to believe that it viii
only be a matter of time before we will de-
velop camera that will record even greater
distances. Before we use 1t, however, we
must have a Photographic plane that will take
considerably higher than 10000 feet because
from that altitude even an object as tall as
Mount Rainier will sink below the horizon at
300 miles.
Shooting at Mount Rainier from distance
greater than that between New York city and
Washington is much like shooting at the moon,
with the difference that you can see the moon.
The principal task is to aim the camera in the
general direction you believe your objective to
be, snap the trigger and hope for luck" What
suck the army captain had on this expedition
was revealed by the remarkable photograph
which Is shown above
Another achievement In this new scientific
marvel Of aerial photography, which was not
so much matter Of luck was demonstrated
during the army air maneuvers over New York
city during May Of this year, the results Of
which shown in the photographs num-
bered three and four above As explained in
the captions, these pictures were taken by ex-
ploding q bomb containing enough magnesium
powder to make 100000 600 candlepower
fash and swapping the shutter at the height Of
illumination
It would seem to be an easy matter to drop
a hashlight bomb and at the moment Of the ex-
plosion to take the photograph. Since, however,
there is definite relationship between the alti-
tude OF the airplane and the height at which
the bomb explodes it Is not so simple. Night
photographs can be taken only at comparatively
low attitudes. Measurements OF the photographs
taken over New York showed the airplane to
have been flying at only 100 feet, although
night photographs could be taken effectively up
70 around 3,00O feet. The lens cannot be left
open until the bomb explodes because lights
from the ground would blur the plates or film.
The only thing the air camera man has to do
at night is TO release the bomb; the rest o. the
details are taken care Of automatically. The
bomb, containing twenty-five pounds Of magne-
SUM powder, is checked in its fall by small
parachute and 4 time fuse sets the interval
bursts the cameras shutter is automatically
tripped by an ingenious mechanical device
Before the World war the science Of aerial
photography, except for a few cases, most Of
which were unsuccessful, was virtually I'M
known 1t took added importance early in
the war and developed rapidly as the airplane
became such an important factor in waging
successful battles But it has been since the
war that its most rapid development has taken
place and that development in this country has
been carried forward mainly by the United
States army.
Although the army is chiefly interested in
nap-making and intelligence photography, each
OF which requires different technique It has
many times sent is camera men and planes to
cooperate wLs other government agencies.
The army has Indirectly aided commercial
aerial photography By developing the best in
technique and in precision of the instruments
In addition to military work, aerial surveys are
used for large variety Of operations Few
pubic utility companies would consider putting
down a new power line without first having an
aerial survey made. Aerial photography Is