Grain.
1. The speckled pattern of silver halide points on the surface of film or paper. Fine-grained material can capture very finely detailed images and coarse-grained material cannot.
There’s typically a relationship between film speed and grain as well. Fast film is more responsive to light because the silver halide clumps are larger and thus the film is grainier. Slower film generally has finer grain. However, film technology advancements in the past two decades have reduced the differences considerably, and today even fairly fast (ISO 800) film has decent grain size.
The term is also used when referring to colour and black and white chromogenic film, though technically they don’t have grain in the traditional sense; they have dye clouds.
cf. fast film, film speed, grain sharp, silver halides, slow film.
2. A unit of weight in the non-metric avoirdupois system. There are 7000 grains to one pound.
cf. avoirdupois.
Entry last updated 2002-04-11. Term 567 of 1487.
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