Posted: Mon Sep 26, 2016 1:07 am Post subject: Re: The lower the iso the higher the contrast |
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Gerald wrote:
alaios wrote: |
"Films manufactured with very fine grain will almost invariably have relatively high contrast, high resolution and low speed"
Ansal Adams , p.19 "The negative"
Can someone explain me why is that ? I thought contrast is a characteristic of film and not necessarily linked to the iso.
Alex |
In a low ISO film the silver halide grains are small and have more or less uniform size. This means the grains have similar individual sensitivity, which results in high contrast. The silver halide grains of a high ISO film have large dispersion of size distribution, and so large dispersion of sensitivity, which results in lower contrast. _________________ If raindrops were perfect lenses, the rainbow did not exist. |