TOMORROW'S LAB TODAY

• Document Type: CREST
• Collection: NGA Records (Formerly NIMA)
• Document Number (FOIA) /ESDN (CREST): CIA-RDP78B04747A001800070040-2
• Release Decision: RIFPUB
• Original Classification: K
• Document Page Count: 10
• Document Creation Date: December 28, 2016
• Document Release Date: June 8, 2011
• Sequence Number: 40
• Content Type: MAGAZINE

1
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RIGHT: You're not looking at the innards
of a brewery, but rather the heart of Cape
Canaveral's center for color motion picture
processing.
OVERALL VIEW of Houston-Fearless motion
picture processing machines
THIS NETWORK of chemical piping is
part of the color bleach reversal system at
the new photo lab. At the left is one
of several safety fountains for quick wash
if personnel become contaminated.
TOMORROW'S LAB TODAY
It seems only proper that Cape Canaveral, America's
kickoff point to the future, should be serviced by
one of the world's most advanced motion picture labs.
by JAMES HUGHES
Executive Editor
In this age of supersonic long-
range missiles, documentary
movies have become important
tools for U. S. Air Force Air
Research and Development Com-
mand scientists.
As permanent records of ma-
jor missile firings, they are used
by scientists to evaluate the re-
sults of tests and to compare
them with the results of previous
firings. When a missile misfires,
films frequently enable scientists
to pinpoint the area or sequence
of error.
In keeping with the impor-
tance of photography to its mis-
sion, the Air Force Missile Test
Center, Patrick Air Force Base,
Cape Canaveral, Florida, recent-
ly began processing film in one
of the largest and most versatile
film processing laboratories in
the world. The $1.4-million fa-
cility can process black-and-white
and color film - 16, 35 and
70mm.
Eleven processing machines,
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Q. How do color films compare with black and
white in regard to graininess?
On this question the experiences of the panel-
ists have led to considerable diversity of opinion.
Purrington states, "No color material permits
print enlargement without appreciable grain [as
compared] to the degree [of enlargement] possi-
ble [when] working with fine grain black-and-
white materials."
Smolka notes, "We have encountered no grain
problems whatsoever with negative films. How-
ever, we have encountered, on occasions, quite
a bit of graininess in certain 35mm direct posi-
tive color films!"
Flanagan considers Kodachrome to be prac-
tically grainless but has observed that graininess
in color films increases with their speed.
Livingood answers "Most color films show
more apparent grain than black-and-white films,"
but he does not consider the graininess of color
films a problem, since other qualities of a color
image outweigh the grain disadvantage.
Morris expresses the view that unless a pho-
tographer was a "miniature" advocate (35mm or
21/2 x 21/1. inches) color film graininess was of
concern only to firms making murals.
Q. What light source should be used for viewing
color prints or transparencies?
Livingood recommends a 4000K light source
for a transilluminator, and suggests that it be
placed in a semi-darkened room. When com-
paring a transparency with a color print made
from it both should be viewed by the same
source of illumination.
Purrington states that when working with art
directors and engravers one should make sure
that the same standard-type illuminator is used
by everyone concerned.
Smolka says "I have heard so many con-
flicting discussions about the most suitable light
source for viewing color prints and transparencies
that I now just follow whatever the manufacturers
recommend."
Q. Are color prints made directly from color neg-
atives suitable as dye transfer prints for use in a)
display b) reproduction?
The answers to this question attest to the fact
that in color work the experts often do not share
the same opinions.
For example, Flanagan replied, "Top quality
Ektacolor prints are as suitable for display as dye
transfers. For reproduction, dye transfer prints
are more easily controlled and corrected. The
quality is also better." Meisel took a different
stand in stating, "Ektacolor prints will serve as
well for display or reproduction as Dye Transfers.
However, notwithstanding contrary assertions by
the manufacturers, we feel that a Dye Transfer
has a greater life expectancy than an Ektacolor
print."
Stanton expresses the strictly personal view
that color prints made directly from color nega-
tives are preferable for display because costs can
be kept within a tight budget but notes, "For
reproduction it has yet to be proved to me that
you can get as good printing plates from negative
color prints as you can from dye transfer prints.
It should be pretty obvious that you have all the
control in the world with dye transfer, whereas
I feel limitations do sneak into the control of
negative color prints."
Purrington voices an "it all depends" approach.
"For display purposes, prints from color negatives
are entirely adequate. For reproduction, some are
and some are not. The question can best be re-
solved by discussing it with the engraver who must
reproduce from the print."
Smolka has complete faith in color transpar-
encies for reproduction purposes. "We prefer to
make direct positive transparencies for reproduc-
tion purposes because of the quality differential.
For some reason or other, engravers and printers
are able to get more sparkle from the transparency
rather than the print. We know, however, that
good reproduction from Ektacolor prints is avail-
able, but where our own pictures are concerned,
we prefer the reproductions from transparencies."
Q. What can be done to salvage a job if color
film is accidentally processed as black and white?
Livingood states that he knows of no way to
salvage a reversal color film if processed as black
and white, but in the case of color negatives he
has found that the silver image can be bleached
back to a silver halide and then reprocessed prop-
erly. He points out, however, that although the
resultant color negative is printable it is way
out in color balance.
Meisel, Morris, Smolka, Flanagan and Stanton
gave the following succinct reply: "Nothing!"
Purrington, as well as Stanton, called attention
to the fact that the Flexichrome Process could be
used to salvage color reversal films that have been
processed as black and white, although consider-
able hand work is involved. Eastman Kodak
outlines a procedure.
Q. What about bleaching o ff-balance negatives?
Can they be corrected?
The majority reply to this question seems to be
that the use of color correction filters in printing
negatives is a more sensible solution. In addition,
Meisel notes that bleaching can be used for off-
color positives. The bleaches recommended are
those from both Eastman and Ansco. Flanagan
warns that the use of bleaches has to be watched
carefully. Slight bleaching can be effective in
making minor corrections but excessive bleaching
can lead to disaster. F1
Industrial Photography - Section 1 ? April 1960 31
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FIRST FLOOR LAYOUT of motion picture processing laboratory, Patrick Air Force Base. 1) Micron air filters and air handling units.
2) Chemical mix room. 3) Chemical analysis room. 4 & 5) 16-35 mm b&w hi-contrast negative machines. 6) 16-35 mm b&w low
contrast negative machines. 7 & 8) 35-70 mm b&w hi-contrast negative machines. 9) 16-35 mm b&w positive machines. 10) Wide
film room. 11 & 13) Wide film dark rooms. 12, 14, 24, & 25) Offices. 15) Chemical storage room. 16) Locker room. 17) Chemical control
console. 18) 16-35 mm color negative machine. 19) 16-35 mm color positive machine. 20) Makeup dark rooms. 21) 35-70 mm rev.
machine. 22) 16-35 mm color rev. machine. 23) 35-70 mm color rev. machine.
compared with four in former
facilities, enable the processing
of film much more rapidly than
in the past. In addition, the new
plant provides complete control
over contamination by an elabo-
rate air and water decontamina-
tion system.
"This is one of the first mili-
tary labs built in an operational
area designed to process film to
commercially acceptable stand-
ards," notes W. F. Bischof,
Radio Corporation of America
production processing manager
and installation project represent-
ative. "This was a complex job be-
cause of the air and dirt problems
that exist here," he added. RCA
functions as a sub-contractor to
Pan American World Airways,
which is responsible for the oper-
ation of the various stations of the
missile test range, including the
launching site at Cape Canaveral.
To clean the water used in
processing, all solid material
particles larger than two microns
- a pencil dot is about the same
size as 50 microns - are filtered
by diatomaceous earth filters.
Mechanical filters in two separate
airconditioning systems remove
all airborne particles larger than
five microns.
E. B. Brady, RCA engineer
who coordinated the building
alterations and machine installa-
tion with the close cooperation
of Major R. L. Jarman, USAF,
AFMTC installation project offi-
cer, lists some facts and figures
to give an idea of the complexity
of the machinery.
"Five miles of chemical piping,
800 valves and 150 pumps trans-
port more than 10,000 gallons
of varied solutions from the
basement to the processing ma-
chines on the first floor," Brady
said. "At the same time, used
chemicals from the machines are
drained to the tanks below for
filtering and replenishment. Each
pipe bears a color-coded marker
with directional arrows showing
flow, source and discharge tanks."
Thermostatic controls hold the
large volume of solutions within
a quarter of a degree of 70
degrees F., well within the toler-
ances allowable in processing mo-
tion picture film. The chilled
water machinery that cools the
basement recirculating tanks
could make 40 tons of ice daily.
One of the several unusual
features in the machinery is the
impingement-type dryer, which
blows a high-velocity jet of hot
air on the film at the rate of
3,000 cubic feet per minute as
the wet film leaves the final wash
stage. This dries the film so
rapidly that it is ready for use
in less than one minute after
leaving the wash.
continued on page Fib
Industrial Photography - Section I ? April 1960
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How to make your own
super black-and-white developer
Plus some notes on how to enhance picture
quality during and after development
There's magic in this formula. We'll
gladly share its secret with you.
But first, a word of caution.
No developer, no matter how good,
will work at its best with any and all film
emulsions. We know this by experience.
We've obtained our experience by re-
searching and making developers and
emulsions under one roof for a long time.
Emulsion-makers and chemists get
together to fit emulsion and chemicals
together. Stringent tests prove when the
fit is perfect.
Made together, tested together, such
materials and chemicals should work
best together, used as recommended.
We know of no better way.
Now to the developer:
Be sure all ingredients are fresh, active,
completely pure. We always test them to
be sure. Also, be sure you don't con-
taminate them while weighing or holding
in storage. These are routine require-
ments to us, ever so important to you.
Buy the best developing agent you
can find. You will be using only a little
of it. Carefully store the rest.
We're recommending two-Elora. and
Hydroquinone. Each does a slightly dif-
ferent job. Together, they complement
each other to do the total job faster,
developing full emulsion speed, maxi-
mum shadow detail, normal contrast,
when used with proper film emulsions.
Use 2.0 grams of Elon, 5.0 grams of
Hydroquinone.
IMPORTANT: Measure these and
all your ingredients precisely, as we do,
in a carefully controlled atmosphere.
We find it's best for quality's sake to do
all measuring in a year-round air-
conditioned room which has undeviat-
ing humidity control. Also, take ex-
treme care not to make mistakes. We
use quality control inspectors to pre-
vent mistakes.
Add an "accelerator." The magical
ingredient that speeds up the de-
veloping process; lets you get out of
the darkroom more quickly. Accelera-
tors consist of such simple chemicals as
caustic soda, sodium carbonate, am-
monia, borax, and others. All are com-
mon, proven in use for a long time.
Use 2.0 grams of granular borax as
your accelerator.
Now, to prevent your developer from
becoming weak too quickly, add a "pre-
servative." One of the more common
preservatives is sodium sulphite, desic-
cated. Use 100.0 grams. NOTE: Be sure
of purity, and exact quantities.
Dissolve ingredients in exactly 750 cc
of water, heated to a constant 125F.
Add water to make a liter.
And that's it! A developer for accom-
plishing sheer wizardry with films like
Kodak Professional Plus-X Pan, Pana-
tomic-X, Tri-X Pan, and others.
It's been tested to work together in a
perfect fit with those films.
This developer (diluted 1:1) will keep
Plus-X grain as fine as advertised. It will
let you take full advantage of that film's
200 working index, without shifting
contrast. You'll see fine shadow detail,
sparkling highlights, delightful middle
tones.
Truly, this is a remarkable developer.
A real "discovery." As remarkable, in
fact, as new Plus-X Film itself.
But why go to all the trouble
of doing it yourself?
You couldn't possibly obtain the pre-
cision, the quality control, the atmos-
pheric conditions of manufacture, all
of which are easy for us. Besides, it will
be less costly to you, less time-consum-
ing, if you let us make it for you.
The fact is, we've been making and
selling this remarkable developer for a
long time. Many professionals are again
"discovering" it because results are
beautiful with Plus-X Film.
This developer is none other than
good old Kodak D-76. Sells for 90 cents
a gallon, processes 30 rolls per gallon
unreplenished.
But note: This time we've recom-
mended D-76 diluted. With Plus-X, di-
lute 1:1 (process approximately 8 minutes
at 68F).
You'll see razor-edge sharpness and a
fineness of grain, almost as fine as with
Kodak Microdol. (Microdol, of course,
requires longer development.)
A do-a-lot developer that works
best with sheet films
Sheet films-professional. They go hand
in hand. But, just as there are different
kinds of professionals who take different
kinds of pictures, so should there be a
developer versatile enough to work to-
gether with sheet films, regardless of
differences in photographer or subject.
DK-50 is that developer.
Professionals, who like to see nicely
graduated negatives because they're the
most salable kind, use DK-50, 1:1.
The result is a kind of contrast con-
trol, so to speak, where the photographer
uses time to his advantage and produces
a negative with good gradation through
tonal range.
Some photographers, interested in de-
velopment speed, get what they want
to see in a negative by using DK-50
undiluted.
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 Approved For Release 2011/06/08: CIA-RDP78BO4747AO01800070040-2
THE MODEL-70/35/16 PROJECTION HEAD ON THE
MODEL C-11 PROJECTION CASE PROVIDES USE OF
70MM, 35MM & 16MM FILM ON 400 FT. ROLLS
? MOTORIZED VARIABLE SPEED "FLOW FILM" FILM
TRANSPORT OVER WIDE SPEED RANGE
? DATA MEASUREMENT AGAINST CROSS-HAIRS IN
IMAGE IN .001 INCH INCREMENTS
? OPTIONAL PROVISION FOR ADDITION OF AUTO-
MATIC X-Y READ OUT TO PUNCH CARDS
STANDARD UNITS ? SPECIALLY
DESIGNED UNITS ? PRECISION
MEASURING STAGES WITH FILM
TRANSPORT ? VIEWERS ? READERS
VANGUARD INSTRUMENT CORPORATION
20 W. Centennial Ave., Roosevelt, L. I., N. Y.
West of Mississippi-Traid Corp., Encino, California
PERFECT LIGHT CONTROL with
RUGGED VERSATILE PHOTOGENIC
modeling, spots, and floods
TOMORROW'S LAB
continued from page 33
Another time and moneysav-
ing step is the rejuvenation of
color film bleach - one of the
most expensive processing solu-
tions. Normally this bleach is
used and dumped. At Canaveral
it is rejuvenated and used in-
definitely.
The machinery - designed,
built and installed by the Hous-
ton Fearless Corporation - can
be altered to permit change-overs
to other processing systems,
should they be required. In. many
instances, duplication of material
has been avoided by using one
common solution in several ma-
chines.
G. M. Powers, manager, RCA
photographic laboratory, empha-
sizes that performance, not size,
is the significant feature of the
new installation.
He sums up the purpose of the
machinery in these words: "Of
course the new processing ma-
chinery increases our efficiency
per man-hour expended, which
is highly desirable. Even more
important, however, is that we
will now be able to give more
dependable and somewhat faster
service to civilian contractors
and military agencies testing
missiles on the Atlantic Missile
Range." E
ELECTRONIC FLASH
continued from page 60
STUDIO MODELING
LIGHT
Accommodates 300 to 1500 watt,
pear-shaped incandescent lamps
- also #4 Photofloods.
Direct light reflector is adjustable
to increase or decrease illumina-
tion for herd or soft lighting. Ball-
bearing caster base stand raises
light from 3610 to 101.
Folding stands available.
FOR 'FURTHER INFORMATION SEE
YOUR AUTHORIZED PHOTOGENIC
DEALER OR WRITE DIRECT TO .. .
NEW and VERSATILE
FILM ANALYZER FOR PHOTOGRAPHIC DATA REDUCTION
16mm, 35mm & 70mm film all in one unit
CP-15 MAZDA
FLOODLIGHT
Accommodates all mogul base,
pear-shaped lamps, 300 to 1500
watts, #4 Photofloods, or movie
floods.
Reflector extension to 9 feet with
ball-bearing swivel caster base
studio stand.
Folding stands available.
F-750 VARIBEAM
SPOTLIGHT
Can be focused from broad flood
to small spot. Rotatable barn
doors, snoots and focusing spot
concentrator available for close-
ups.
Extendible to 91/2 feet - adjust-
able bracket available for opera.
tion at lower levels.
Folding stands available.
-- ? ? - ~ 1.
phy, our exposure depends on
the total light. Therefore, we add
the element of time and get such
terms as Beam Candle Power
Seconds (BCPS). This is the
term we use for rating electronic
flash units. This gives the
strength of the light on the beam
of the reflector. For instance,
2000 BCPS is the strength of
the light on the beam and is
equal to a light source of 2000
candle power acting for one sec-
ond. For those so inclined, it
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4011111, Ask
with a liberal arts education be-
forehand. Unfortunately most
straight photography courses to-
day fit young people for photo-
journalism or advertising pho-
tography rather than my field."
He also advocates that a photog-
rapher anxious to enter industry
he in business for himself some-
time during his career.
Kinstler's background is an
example of what he is talking
about. He became interested in
photography at the age of 15
and free-lanced for local news-
papers. Later this led to a sum-
mer job as relief cameraman for
the local daily newspaper. In
1938 he was partner in a com-
mercial photography studio and
from there joined Wright Aero-
nautical Corporation as junior
metallurgist.
1!)uring World War If he
headed a staff of five men in an
experimental photo lab who were
given the assignment of record-
ing progress in the development
of underwater detection devices.
After the war he received a BA
at the University of Cincinnati.
Not content to put in eight
hours a day supervising photog-
raphers, his spare time is taken
up with such activities as writing
a scholarly thesis titled "The
Role of Functional Photography
in Industrial Communications"
and presenting papers on techni-
cal photographic applications to
professional groups. An energet-
ic speaker, he is much in demand
around the country and has
spoken before hundreds of pho-
tographic organizations. He was
on the staff of the Industrial
Photography Management Sem-
inar at the Winona School.
Only a sense of humor and
affable personality keep Kinstler
on an even keel during his
peregrinations around the coun-
ter and the carrying out of his
numerous activities. He is mar-
ried, with three sons, and lives
in Cincinnati. Richard C. Kinst-
ler is one of the growing breed
of men on whose shoulders rest
the responsibility for running
photo installations in multi-mil-
lion dollar companies. ^
NEW! CONTINUOUS "THRU-THE.
LENS" REFLEX BRILLIANT VIEW.
ING - FOCUSING . . "Front-of .
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Para! l ex!
NEW! 8 TIMES MAGNIFICARTIO
OF REFLECTED IMAGE . .
yy, sealerl
optical system is plight-tight
-fool proof and
NEW! VARIABLE SHUTTER FROM
180? TO CLOSED ... Controls ex
posure perfectly for smooth fades,
lap dissolves, etc. Safety signa.
sounds when shutter is completely
closed!
NEW! VARIABLE SPEEDS ONTIN
UOUS FROM 8 TO 80 FPS
NEW! BIG 3-LENS TURRET.
all . , take.;
11 mtn C-mount lenses thou ;
additional viewer! Has special lock.
ir~g device!
Industrial Photography - Section 1 ? April 1960
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THIS FREE DEMONSTRATION DISC
can be the beginning of a better soundtrack for your film. ;Vlore
and more producers are turning to HI-Q for the answer to their
musical needs, for Hi-Q represents the finest library of background
music available . . . licensed for all film media . . . contained on
tapes and corresponding reference discs.
A complete package that can be expanded to your
specifications.
If you produce films of any nature, write for this
demo (it's free, of course).
Capitol Library Services, Hollywood & Vine, Hollywood 28, Calif.
Time-honored Pathe for the Professional
whose livelihood dep6nds on best re-
sults from every assigoment..Top qual-
ity work is assured! Arid for flexibility
under all conditions the Tropics, Arctic,
etc., the Path6 has no,peer. Of course,
it's compact, rugged, and lightweight,
with fast simple unexcelled loading and
is adaptable for special motor i zation.
Preferred by photographers, for nor-
mal, intricate, scientific, and special in-
dustrial assignments. Attractively
Priced. Guaranteed. .
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132 pg. Encyclopedia of "Photo Tools"
13URKIE SL JAMES, IPAC
 Approved For Release 2011/06/08: CIA-RDP78BO4747AO01800070040-2
A Silver-Recovery Apparatus for
Operation at High Current Densities
NICHOLAS J. CEDRONE
REPRINTED FROM JOURNAL OF THE
SOCIETY OF MOTION PICTURE AND TELEVISION ENGINEERS
Vol. 67, No. 3. pp. 172-174, March 1958
HI-SPEED EQUIPMENT, INC.
73 Pond St., Waltham 54, Mass.
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 Approved For Release 2011/06/08: CIA-RDP78BO4747AO01800070040-2
A Silver-Recovery Apparatus for
operation at High Current Densities
'Silver recovery systems operating at the higher current densities require thorough
solution agitation at the cathode surface in order to deposit metallic silver con-
tinuously. In the apparatus described, agitation is provided by an external pump.
With the solution nozzles located tangential to a cylindrical cathode, high surface
velocity is attained and mass flow held to reasonable values. Thus, the problem of
excessive mechanical energy input is avoided, while the scrubbing velocity pro-
vided permits current densities as high as 10 amp/sq ft.
_ f,P-r CIr.YTiC silver-recovery systems
may be separated generally into two
classes: those which operate at low cur-
rent density with no solution agitation,
and those which operate at high-current
densities with vigorous solution agitation.
Low current density systems operate
;It 50 ma to 4(10 ma/sq ft of cathode ,I
but the higher currents are generally
avoided. Since the permissible plating
t ate is affected by a variety of conditions,
such as bath composition, silver con-
centratti and gelatin concentration
among others, and since these factors
may vary considerably, nonagitated
system, are usually operated at current
densities of 50 ma to 100 ma, a range
which is satisfactory for nearly all con-
ditions. The systems are operated with-
out careful control or supervision, and
are best suited for processing rates
which yield 2 to 3 oz of silver per day.
If we Lake a typical system operating
with a sodium acid hypo bath, current
density would he approximately 0.1
amp/sq ft of cathode. Assuming a typical
current efficiency of 90rJ%, a cell would
require 100 sq ft of cathode surface in
Prrsente-l on May 1, 1)57, at the Societc's Con-
vention at Washington, D.C., by Nicholas .1_
(ledrone. Hi-.Speed Equipment, Inc.. 73 Pond
Sr., WaLham 54, Mass.
( t'Lis p;,per vvas received on :'lugnst ,, 1957.)
order to accommodate a film-processing
rate of 1000 ft of 35mm film per hour.
'I Iris indicates that low current density
sa stems could not be employed in most
(notion-picture laboratories on the basis
of space requirements alone.
In order to obtain recovery rates which
arc of practical interest to motion-pic-
ture laboratories and other film labora-
tories where the film-processing rate
yields 20 oz or more of silver per day
(equivalent to 20,000 ft of 35mm film),
it is necessary to turn to he other class
of electrolytic systems, those which
are vigorously agitated and operate at
hither current densities.
the chemistry of hypo baths during
electrolysis is very complex and has been
thoroughly presented elsewhere.1,2 For
our purposes, it is sufficient to note that
thr typical sodium hypo or ammonium
hypo bath found in continuous processing
machines is subject to electrolysis at
pr.ctical rates by merely providing the
pry 'per physical conditions of vigorous
agitation and continuous filtration.2
A typical sodium acid hypo, which will
tolerate 200 ma!sq ft without sulfiding
under, static conditions, will tolerate on
the order of 10 times this current when
agitated to provide a velocity of 1 ft see
relative to the cathode.
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By NICHOLAS .1. C ,ET)RONF
Because of the high current dent ties
which agitated systems will tolerate, it is
possible to use them effectively in hypo
systems containing several hundred ;al-
Ions and which fix as much as a mil: !.ion
or more feet of film per day. These re-
covery systems are more efficient in to rms
of weight of silver recovered as a rer-
centage of total silver available ant in
terms of reduction of hypo costs-
Recovery Systems
Recovery systems operating at the
higher current densities will toles ate
current according to the silver concen-
tration of the solution and the rate of
solution agitation. Figu:: e 1 shows the
relationship between current density , nd
the silver content, with the solution veloc-
ity held constant at 1 fi_ sec.' Figur? 2
shows the relationship between current
density and agitation, with silver contenI
held constant at 2.2 g/1.' In order for
recovery to proceed at current densities
in excess of I amp,/sq ft, continuous fil-
tration is also necessary tr remove tra -vs
of sulfide which form intermittently at
the cathode surface and would u ti-
mately accumulate to an extent which
would reduce the effective plating ai ea
or would eventually "poison" the ent re
plate.
The various arrangements for p o-
viding agitation have been listed by
Hickman2 as follows:
(1) air or gas bubbled between the
electrodes;
(2A) rotating cathode, ~tatiom, rv
anode; or
(213) rotating anode, stationary calh-
ode;
0 .33 .66 I 1.33 1.66 2 2.33 2.0(6
;TRAMS AS PER LITER PERIPHERAL SPEED IN FEET PER SECOND
Fig. 1. Relationship between permissible current Fig. 2. Relationship between permissible current density and surface
density and silver concentration, velocity at the cathode.
172 March 1958 Journal of the SMPTE Volume 67
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 Approved For Release 2011/06/08: CIA-RDP78BO4747AO01800070040-2
(3) paddles moving between anode and
cathode;
(4) external pump stirring; and
(5) external paddle stirring.
At least one design based on each
of the foregoing methods has been
constructed and used. A recovery cell
employing air turbulation was the first
successful cell used in a motion-picture
laboratory and was designed by Garbutt
& Associates.' This design comprises a
rectangular tank with alternate carbon
and monel plates reaching across the
narrow dimension and hanging down in
the fluid. Air tubes are positioned be-
tween the plates at the lower extremities
and release air blasts to provide the
required agitation. Hickman points out
three shortcomings of the air-agitated
system.2 The cathode is depolarized;
the bubbles occupy space, reducing the
effective plate area; and the foam pro-
duced tends to wet the electrode hangers.
An example of the rotating cathode
design is set forth in a patent by Lever-
enz.b Essentially, this comprises a tub
which may be the cathode, or a tub con-
taining one or more concentric cylinders
which form the cathode. A beam lies
across the top of the tub and mounts a
motor driving carbon anodes which are
suspended in proximity to the cathode
cylinders by a spider structure. Agitation
at the surface of the cathode (both
inside and outside each cathode cylinder)
is provided by the action of the carbon
anode sweeping past.
An example of the rotating anode
method is shown by a device described
by Duisenberg. a This consists essentially
of a series of stainless-steel disks threaded
onto a shaft with spacers to keep the
disks separated by approximately 2-in.
Two slabs of carbon with the long
dimension parallel to the shaft complete
the array and the entire assembly is
suspended in a hypo tank. In the design
described, rotation of the shaft at a
speed of 179 rpm provides the required
agitation for an average maximum cur-
rent density of 2.5 amp/sq ft. Systems of
this type generally provide excellent plat-
ing but require disassembling in order to
remove the silver.
The design which uses paddles moving
between anode and cathode is probably
the most familiar of all. Systems of this
design are widely used by the larger
motion-picture laboratories and were sup-
plied by Eastman Kodak Co. as Model 1
and Model 2. The Model 1B (known as
Hickman Cell) consists of a rectangular
tank approximately 24 by 50 by 28 in.
fitted with alternate carbon and stainless-
steel plates, spaced about 2 in. apart,
which reach across the narrow dimension
of the tank and are suspended into the
solution. The plates are slotted to permit
straddling a shaft which carries sets of
paddles arranged to occupy the space be-
tween the alternate plates. In the par-
ticular system described by Hickman,'
Fig. 3. "Silver Tower" assembly complete with recirculation
pump and sump tank.
the shaft carrying the paddles is rotated
at about 80 rpm which permits a total
current of about 200 amp on a total sur-
face of 90 sq ft for an average current
density of approximately 2.2 amp/sq ft.
By reducing the size of the cathode and
making the cathode from a series of rods
rather than a flat sheet, higher currents
can be tolerated because of the more
turbulent agitation resulting from the
discontinuous surfaces. In one design,
alternate rows of carbon-rod anodes and
stainless-steel cathodes are used and
agitation is provided by a standard or
conventional propeller mixer mounted
over the side at one end of the tank and
positioned so as to direct flow in a path
around the inside of the tank.'
External Pump Agitation
The principle of increased turbulence
resulting from discontinuous cathodes was
used in a design by Doran to obtain
effective agitation by an external pump.7
In this design, a rectangular tank is
fitted with alternate rows of anode rods
and cathode rods which are suspended
from beams reaching across the top. The
solution is withdrawn from one end of the
tank and pumped back in at the other
end. Since the tank cross section is so
large compared to pipe-line area, aver-
age solution velocity through the tank is
low but the discontinuities provided by
rods create sufficient turbulence to allow
plating at rates suitable for motion-pic-
ture laboratories.
Another application of external pump
agitation is one discussed by Hickman in
which solution is recirculated by a
centrifugal pump and discharged through
nozzles placed between the plates. This
arrangement was not considered success-
ful because of high pump-power require-
ments and inferior plating relative to
other systems.
A more recent example of external
pump agitation is seen in the Model S-5
Silver Tower manufactured by Hi-Speed
Equipment, Inc. The Tower comprises a
cylindrical cathode and anode mounted
concentrically on an insulated base plate
(Fig. 3).* The Tower assembly is ap-
proximately 43 in. high and is mounted
across the top of a sump tank which is
approximately a 27-in. cube.
Hypo from the sump tank is pumped
to the Tower through two nozzles which
are tangentially located at the Tower
base. These nozzles discharge into the
annular space between the anode and the
cathode and the solution is directed into
a circular flow by the cathode. Because
of the high kinetic energy of the fluid
stream as it leaves the nozzles, the fluid
continues to swirl and climbs in an
ascending helix. This motion is repre-
sented by the arrows in the diagram
(Fig. 4). Vanes located at the top of the
anode deflect the fluid at four points and
cause it to cascade toward the center of
the Tower where it falls into a filter sock
suspended concentrically within the
anode. The fluid runs downward into
the sump and is again recirculated by the
centrifugal pump.
Velocity at the nozzle is calculated as
39.7 ft/sec. At the point just above the
lower end of the cathode, the velocity
in a horizontal plane is 9.8 ft/sec. At a
point just below the top surface of the
fluid, the velocity in a horizontal plane is
3.5 ft/sec. These velocities are obtained
with a mass flow of 82 gal/min.
The combination of horizontal inlets
and cylindrical cathode provides high
surface velocity with relatively low mass
flow.
By way of contrast, if the anode and
the cathode were both unwrapped and
made into flat sheets while maintaining
the same area, the same height, and the
same space between the two, we would
find that a mass flow of 1000 gal/min
would be necessary to provide an average
velocity of 3.5 ft/sec over the cathode sur-
Cedrone: Silver-Recovery Apparatus for Operation at High Current Densities 173
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 Approved For Release 2011/06/08: CIA-RDP78BO4747AO01800070040-2
SILVER RECOVERY
SYSTEM
INSULATING
FLANGE
(PLASTIC)
face. The technique of circular fow is,
then, clearly an effective means of reduc-
ing the pump horsepower without nar-
rowinK the anode-to-cathode space to
the pcint of inviting treeing and short
circuiting.
In operation, silver is plated continu-
ously on the inside of the cathode and
the solution is filtered continuously as it
cascades through the center of the anode
back to the sump tank.
Because the surface velocity in the
'lower is considerably higher than in
,.cost "high-turbulation" systems, the
normal current densities are also corre-
spondingly higher. After an initial cover
of bright plate is formed on the wetted
surface of the cathode, the current is
gradually increased as allowed by the
silver concentration in the hypo. Current
densities of 10 amp/sq ft have been main-
tained with acid hypo containing slightly
more than 2 g of silver per liter. Ordi-
narily, the current is held to approximately
/0 amp for a current density of 5.8 amp.
This i$ in keeping with the widespread
practice of providing an extra margin of
safety in the operation of silver recovery
systems so as not to endanger the hypo.
At 70 amp and 75% current efficiency,
approximately 6.8 troy oz of high-purity
silver would plate on the cathode each
hour.
The lowest velocity in the lower
occurs near the top of the cathode in the
region above the anode. This area is,
therefore, most susceptible to sulfiding
and offers a convenient point for check-
ing plate color and texture. Plating in
the less visible region lower in the annular
space will generally be as good or better
than at the top, since surface velocity is
higher towards the bottom..
When operating close to maximum re-
covery rates, the Hi-Speed Tower pro-
duces silver with a surface texture ap-
proximately that of line sandpaper and
with a tan color. The color was at first
assumed to indicate imminent sulfiding.
However, the color was not locked in
with the plate but rather was in the form
of a surface haze which required only
gentle scraping to reveal bright silver
directly underneath. This color was
attributed to the oxidation products of
carry-over developer as reported by
Sharpe,' particularly since silver plate of
this appearance was analyzed as over
99% pure silver.
After the silver plate has accumulated
to a thickness of ii in. or more, the cath-
ode is lifted from the Tower and the
silver is removed. The bond between
silver and stainless steel is normally a
poor one. However, in the present case
we have a cylinder of silver encircled by a
cylinder of stainless steel. The silver is
locked in place by what is, termed "arch
action" with each bit of silver acting as
the keystone for its neighbors. This effect
is an advantage while the cell is in opera-
tion because it prevents chunks of silver
from falling away and possibly shorting
the cell. To remove the silver, it is of fly
necessary to chip out a narrow st-ip
with a mallet or spatula and thus eff !c-
lively remove the "lock" holding he
silver. Large sheets of silver can then be
peeled inward without difficulty.
This equipment is the result of an
attempt to design a silver-recovery s;s-
tem which would require a minfmt. im
maintenance, yet permit high recov, ry
rates. The first models fell short of 1 he
goal and were susceptible to shortiiig
An improved design followed in wh ch
the anode-to-cathode space was n-
creased to 2 in. and the method of n-
sulating the base was changed from r fib-
ber to PVC (polyvinyl chloride). With
the shorting difficulty eliminated, he
pump appeared to be the only remain-
ing source of possible difficulty and a
sturdy, conservatively rated unit i ras
selec ted.
Units of the current design have b! en
in operation for over one year without
any breakdown or maintenance prob-
lems reported.
Acknowledgment
The author wishes to thank H. E.
White of Eastman Kodak Co. for inl Jr-
mation and comments pertinent to he
design.
References and Bibliography
1. A. A. Rasch and J. I. Crabtree, "Electro-
lytic recovery of silver from fixing bath., at
low current density," Phot. Sci. Tech. ,S'erie II,
2: 15-33, 1955.
I. K. Hickman, W. Wyerts and 0. E.
Goehler, "Electrolysis of silver-bearing t tio-
sulfate solution," Ind. Eng. Chene., 25: 2 32-
212, Feb. 1933.
3. K. C. D. Hickman, et al.. "Method for the
recovery of silver from used photogralihic
fixing solutions by electrolysis," U.S. 'at.
1,954,316, Apr. 10, 1934.
4. F. E. Garbutt and T. M. ILrgman, "Mel cod
and apparatus for recovering silver f om
fixing solution," U.S. Pat. 1,866,701, Mar.
13, 1929.
5. Wilhelm Leverenz, "Process and equipn.ent
for electrolytic regeneration of exhau ted
photographical fixative haths," Cana,: tan
Pat. 491,453, Mar. 24, 1953.
6. Charles E. Duisenberg, "Silver recovery md
prolongation of fixing baths," Jour. SME'TE,
65: 429-431, Aug. 1956
7. A. B. Doran, "Method and apparatus for the
recovery of metal from a liquid," U.S. 'at.
2,158,410, June 1935.
8. C. J. Sharpe, "The formation of colo. red
solutions during electrolysis of used firing
baths," Brit. J. Phot., 101. 140, 1954.
9. K. C. D. Hickman, "Method for plnto-
graphic processing," U.S. Pat 1,905,67,
Apr. 25, 1933.
10. K. Hickman, C. Sanford and W. Wy rts,
"The electrolytic regeneration of fi :ing
baths," lour. SMPTE, 17: 568-590, act.
1931.
174 March 1958 Journal of the SMPTE Volume 67
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