Evening star. [volume] (Washington, D.C.) 1854-1972, 1952-02-17
Camera Angles
Troy and Tank Developing
By Alexander J. Wedderburn
curofor Of Photography
The Smithsonian Institution

tive but the roll may be cut into
easy-to handle lengths. As In the I
case Of the cut films, the indi.
vidual negatives or lengths Of film
should be wiped free of scum be-
fore hanging up to dry. Use .
viscose sponge or absorbent cotton
and do the wiping under water.
The Developing Tank.
After you have tried q few times
you will decide 1t is high time for
you to get q ron film developing
tank. These are small tanks made
Of hard rubber. plastic or other
composition, containing q reel up-
on which the strip Of film may DO
wound. Once the film Is on the
reel and the tank closed the entire
operation can be conducted with
the lights turned on. The tanks
are light-tight and the liquids
may be introduced and drained on
through baffied openings.
First, after the paper backing
has been removed. the roll Ii
wound on the reel, which is then
inserted into the tank. Once the
lid Is locked into place you can
turn on the light and go to work.
The developer is poured In and
allowed foreman for the required
number Of minutes-then drained
of. The short-stop goes In next
and. in turn. is drained on after
"a few moments. Finally, YOU pour
in the fixing bath. When fixation
is complete the tank may then be
opened and the film handled as
described above for washing and
drying.
When cutstilm is to be processed
in quantities In excess Of six
sheets, the tank method should be
used. Here three deep. hard rub.
Der tanks-open at the top-are
required, each filled with one Of
the three solutions. With this type
tank all work Is necessarily done
In complete darkness. The Aim
holders should be unloaded one at
q time with the films going imme-
diately into the hangers. Film
hangers are metal frames by which
the films are suspended In the
tanks. When the frames are
loaded all should go into the tank
developer at one time for uniform-
ity of development.
Clearing Away Air Bells
II you are handling a film
hanger for the first time you will
notice that the upper bar extends
beyond that Of the base forming
two projecting arms. These arms.
rest on the sides of the tank,
holding the films in suspension in
the solution. At frequent inter-
walls during development you
should pick the hangers up by
these arms and allow them to
drop back against the tank. This
WIN Jar loose any air bells that
may form on and cling to the
sheets Of film. Without this con-
slant agitation, the air bells will
prevent development at the point
LOT contact. The result will be So
called ''pinholes" through the
emulsion that will turn I'D as
black spots on the prints.
The rest Of the process is similar
to what we have already desc1bed
with the films going into the
shortstop. then the fixing bath
and finally the water. About
the only exception is in the hand
ling Of the films during washing
and drying. They remain In the
hangers until dry. A fourth tank
lis simply placed under water tap
and the running water Is allowed
to circulate among the negatives.
At the top Of each arm Of the film
hanger you viii notice a notch.
This has been provided so that the
hanger may be suspended from a
wire or other line for driving