Complete Film Development Process
Beyond the essential sequence of development, stop, fixing, and washing, professional practice includes further stages, intended to perfect the stability and long-term preservation of the negative. This guide sets forth the entire sequence.
We have already set forth, in another guide, the essential sequence of the photographic process: development, stop, fixing, washing. Whosoever wishes, however, to conduct their practice with the rigour proper to museum archiving, or who treats materials intended for long preservation, would do well to know the entire professional sequence, of which the essential sequence forms but the central core.
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The Complete Sequence, Stage by Stage
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0) Pre-soak (3-5 min).
An optional water bath preceding development proper. It evens out the temperature and saturation of the emulsion, favouring a more even development.
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1) Development (4-16 min).
The stage that transforms the latent image into a visible one. The exact time varies greatly according to the product and film employed: always refer to the specific technical sheet.
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2) Stop (1 min).
Abruptly halts the developer's action, protecting the fixing bath from alkaline contamination.
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3) First Fix (2-5 min).
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4) Second Fix (2-5 min).
Professional practice prescribes a double fixing bath: the first, already partly spent from previous use, does the greater part of the work; the second, always fresh, completes its action, ensuring every trace of undeveloped silver halide is removed. Once the first bath is exhausted, the second takes its place, and a fresh fixer occupies the position of the second.
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5) Wash (4-10 min).
A first wash, intended to remove the bulk of residual fixer.
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6) Toning (1-2 min, optional).
For whosoever desires a change in the colour of the silver image, or an increase in its stability over time.
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7) Rinse (1 min).
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8) Washing Aid (2 min).
An intermediate bath that favours the subsequent removal of residual fixer, considerably reducing the time and water volume required for the final wash.
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9) Final Wash (12 min).
The concluding wash, bringing the negative to a level of purity suited to long-term preservation.
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10) Wetting Agent.
A final bath that reduces the surface tension of residual water, favouring even drying.
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A Note on Simplification
Whosoever does not require museum-grade archiving may legitimately limit themselves to the essential sequence (development, stop, fixing, washing, wetting agent), omitting the double fix, toning, and washing aid. The stages set forth here in full represent the highest degree of care, not an obligation for every photographic practice.