Evening star., 1949-07-17
Darkroom
By Alexander J. Wedderburn
Curotor OF Photography
The Smithsonian Institution


humid. He was having all kinds
of trouble with his Aim and
paper with emulsion running, re-
ticulation patterns forming all
over his best negatives. and other
woes of q similar nature. So we
hashed over a number OF hot
weather processing theories and
our friend finally went of in a
happier frame of mind to try his
luck again.
Now none OF US likes to 60
around looking for trouble but
it behooves us to look ahead and
foresee. If possible. any trouble
that may crop up IN the dark
room to spoil our best efforts with
the camera.
When the sun broils and the
humidity goes berserk, we have
good reason to fear for both
equipment and the pictures pro-
duced thereby. The humidity
does it's dirty work to the equip
ment and film while excessive
Temperatures make darkroom ac-
tivities a nightmare Of futility If
you are not we'll prepared. So
let's look at the pitfalls ahead
and see what we can do to avoid
them. The prevention isn't much
Of a problem.
TrnuiraI-pasked Film.
Almost any one who has shot
pictures In q tropical climate is
familiar with tropical-packed Aim.
For the next few weeks. humidity
will probably be Just Is tough
around here and at most vacation
spots as 1t is in the tropics. Ac-
cording to the books. Aim and
Photographic paper Is best pre-
served at q relative humidity Of
40 per cent. So, right at the out
set, If you do any amount Of proc
essing In the summer or even If
you have your f1lm handled else
where 1t will be a very good idea
to carry the tropical-packed item.
And let's not overlook an assist
for your trusty camera. exposure
meter and filters. They are sub
ject to the effects Of humidity.
Fungus is the great foe of camera
equipment in any warm. moist
climate. It generally attacks the
cement between the elements of
your lens. It similarly attacks
your filters and, If not prevented,
can cause lot Of trouble and ex-
pense. Take = few simple pre-
cautions II your equipment will be
exposed to the described condi-
tions. First. and most important.
under no conditions store or leave
your equipment in q damp or
moist place. II your camera
should become wet, be sure TO dry
1t out thorougly and don't forget
that sunlight is the worst enemy
Of mold-sun your equipment fire.
quently In humid weather.
Secondly. 1t will pay dividends
II you pack your equipment In q
container that has q canister OF
silica gel to absorb the excess
moisture. If you can't obtain 1t In
canisters. tuck Q bag of 1t into
your equipment kit during the
summer months. After the film
has been exposed you can safe
guard 1t with silica gel. Tropical
packing isn't too effective once 1t
has been opened 50 don't count on
this alone. And don't get the idea
that the tropical packing will allow
sou to leave your film In your
locked car-particularly IN the
glove compartment; car tempera-
lures sometimes rise TO lz5-14o
degrees In the sun.
Guard Against Heat.
Tropical packing will effectively
protect against humidity but is no
safeguard against excessive heat.
Do not leave your flm for any
length Of time. either In the
camera or in film holders. If you
use them. In hot. moist weather
the Aim will stick and become
damaged on removal.
Hot-weather processing calls
for strict attention to solution
temperatures (s8-7o degrees Is
ideal and should be the goaD
But regardless Of whether you
can manage to keep the solutions
down to that average, be sure that
each Of the solutions Is the same
temperature as the others. If
there is much disparity. reticula-
ton will surely take place. The
same thing can happen If the
temperature Of the darkroom is
greatly different from that Of the
solution.
We realize that situations will
arise when ordinary tap water is
too warm for Photographic use.
But this is not the signal to sur
render. Instead you can use one
Of several methods to bring your
solutions down to their proper
temperature level. One way is to
chill the water with cracked ice.
This is not accomplished by add
Ing Ice to the developer or other
baths. or dilution would take
place. Instead. place the tray of
soup" in another larger tray of
ice or ice water. Or you can
lower a jar of cracked ice into
your tank of working solution. If
no ice Is available try stirring a !
good bit of hypo into the outside
container since this chemical
lowers the temperature of water
as 1t dissolves.
Special Solutions.
You may find yourself in a posi-
don some day when you have no
Cameras
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