The DARKROOM COOKBOOK, Third Edition

Film Development 47
These disadvantages have led to attempts at discovering developing agents, and combinations
of other agents with ppd, that would give superfi ne grain results and shorter development
times without the troublesome properties. Three such agents are glycin, o-phenylenediamine,
and diethyl-p-phenylenediamine bisulfi te.
Glycin, used in combination with ppd (Formulas: Superfi ne-Grain Developers: DuPont
No. 3 Superfi ne-Grain Developer), makes a fi ne-grain developer with improved emulsion
speed and faster rate of development. Unfortunately, because of the presence of ppd, it still
suffers from the unpleasant side effects of high toxicity and staining.
o-phenylenediamine (opd) is one of the more successful replacements for ppd. It has
weak developing properties but is a good solvent for silver halide. In the Windisch Superfi ne-
Grain Developer, metol acts as the primary developing agent for the silver halide. The opd
works on the silver being developed, dissolving any extraneous unexposed halide and resulting
in superfi ne grain.
Geoffrey Crawley’s FX 10 makes use of a ppd derivative, Kodak CD-2®, commonly found
in modern color developers. As a developing agent, CD-2 works faster with less tendency to
stain than ppd but is not capable of producing as fi ne a grain.
As far as the general composition of superfi ne grain developers, nearly all of them have a high
sodium sulfi te content as sodium sulfi te is an effective silver solvent. For an alkali, they use small
quantities of either carbonate or borax in order to minimize the energy of the developer and
produce a fi ner grain. FX 10 uses a buffering mixture of borax and boric acid, whereas Windisch
Superfi ne Grain Developer uses sodium metabisulfi te to reduce the pH of the sodium sulfi te.
Tropical Developers
With most developers an increase in temperature means increased rate of development,
increased danger of fogging, and excessive swelling of the gelatin emulsion that could
result in its melting away. The faster the fi lm, for example Tri-X, the more susceptible it is to
increased fogging at high temperatures.
There may be times when it is not possible to cool solutions to below 80F/27C. This
includes photographers working in non-insulated darkrooms during the summer where a
water-cooling system is not available and those working in the tropics. Should this situation
occur there are special developers known as “tropical developers” and modifi cations that can
be made to other developers for extreme heat conditions. Tropical developing formulas prevent
excessive swelling of the gelatin, either by the addition of a substance that reduces swelling
or by eliminating those that cause excessive swelling. Tropical developers often include
sodium sulfate and extra antifoggant.
When processing at high temperatures a mildly alkaline, buffered borax developer is
recommended. Alkali-free developers of the amidol type or one of the mildly alkaline fi ne
grain developers such as Kodak D-23 are preferable to those with normal alkali content.
Additionally, a pre-hardening bath such as Kodak SB-4 Tropical Hardener Bath or a specially
formulated tropical developer may be used.
Modifying Developers For Tropical Development Most developers can be made suitable for use at high temperatures
(up to 95F/35C) through the addition of 105.0 grams of sodium sulfate, anhydrous,