Low ISO films generally need shorter development than high ISO films of similar basic design - a consequence of their thinner emulsion layer and higher native contrast.
I suppose the silver halide particles are smaller in slower film, and therefore have a a larger surface-to-volume ratio. Hence the developer will work faster on the smaller particles.
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.
