Evening star. [volume] (Washington, D.C.) 1854-1972, 1927-01-06
SUB SEA PICTURES
UNNATURAL COLORS
Geographic Staff Takes Pho
tographS of Fish in Ma
tive HauntS.

Eight illustrations in the National
Geographic Magazine for January are
the first published natural-color pho
tographs made beneath the surface OF
the sea. They represent many weeks
and months of experimentation by DIR
W. III. Longley, noted ichthyOlogist
OF GouCher College. and Charles Mar
fin Of the Photographic laboratories OF
the National Geographic Society.
The conditions encountered off Dry
Turtuga&, of the Florida Keys, neces
Stated the development of q special
technique for this unique Photographic
Undertaking. because the ordinary
GutoChrome plate would not register
the moving life under water. 1t was
necessary to hypersenSitiZe all plates
used in shallow depths, SO that the
HnderSea exposure m ght be reduced
81 a twentieth of a second.
owing to the dampness, the eXces-
EiNc heat and the lack of sufficient
power at Dry Tortugas to operate an
electric fan properly, the sensitizins
had TO I've undertaken each morning at
O'Clock Uhe coolest time of the day.
% prevent the emulsion on the glass
plates from melting.
Flash Powder Used.
when the scientists attempted to
make autochromes at depths of as
much as Is feet it was found that,
owing to the greatly reduced power
Of sunlight, even the hypersensitiZed
plate would not give satisfactory re
suits. 1t became necessary to supple
ntent and intensity the sunlight. Mr..
Martin therefore constructed a flash
light powder mechanism which could
nc t1of hI- a Snl ayl1p
tographer at the exact moment of his
finny subjects best posings. The adj
ditional illumination made possible au-
f1chrorleS on plates which had not
been hyperSenSitiZed.
One problem which had to be solved
was to synchronize the discharge of
the i7ashight powder with the camera
shutter. SO that the latter would be
wide open the instant that the flash
had reached it's illumination peak.
4 pound of magnesium powder was
used for every charge. The ignition
of such an amount of dazzling eXplo-
sive on a dory piloted by two men,
who were forced at the same time to
follow the ShadowT movements of the
diver with his camera far below. was
more than human nerves could stand.
Especially was this true when it some
times happened that the men in the
boat had to wait for two or three
hours, every moment anticipating the
binding and deafening defamation.
They could never know at what in
slant the diver would find his quarry
in the desired position with respect TO
his lens.
Burned i'm Explosion.
To overcome this nerve-racking sus-
S1arSp cr11nl TonrnofqG GOn-
structed to support a drycell battery
the fashlight powder and the reflector.
The contrivance. floating upon the
surface and guided here and yon,
could be handled by the diver himself,
leaving the men in the dory free to
follow their colleague under sea at a
safe and comfortable distance from
the powerful explosive yet near
enough TO maintain the necessary flow
Of air pumped to the man beneath the
surface. The mere setting of the cleo
{rical connections, however, within
few feet of the big charge of powder
was : hazardous undertaking.
On one occa sion DIR. Longley was
seriously burned and incapacitated for
six days by a premature explosion OF
an ounce of powder. Had it been a
full charge, the accident would prob
pblv have been fatal or resulted In
permanent blindness.
The camera used in making these
autcchromes was inclosed in a brass
case with plain glass window" in
front of the lens. A supplementary
hood was fitted above the regulation
reflector. and by means of an acute
angle mirror the photographer was
able to focus his instrument. looking
directly in front Of him instead OF
bending over the camera, a movement
which would have been extremely diff
cult while wearing the divers helmet.
BY untiring effort and patience
came success in a new field of nat
ural-color photogra ply.