agitation
Definition: Noun: (1) irregular or random movement of processing liquids over material being processed. * Normally intended to replenish exhausted chemicals with less exhausted or active chemicals. (2) process of causing or ensuring a random or an irregular movement of processing liquids over the material being processed. * Methods include (a) inverting processing tank (in hand-processing) (b) blowing inert gas e.g. nitrogen through processing bath (c) stirring chemicals either with paddle or through action of rollers transporting film or paper (d) tilting processing dish (in hand-processing of prints or large-format film).
Agit-propre
Agitation in daylight tanks varies considerably depending on how full the tank is, particularly with tanks that hold three or more reels of film. When processing only one film in a multiple tank, you should (a) load empty reels in and (b) fill the tank with as much liquid as you would for a full load of film. If not, you will be giving far more agitation than a with full tank.
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