Response to Acros in Microphen - and why are ISO ratings inflated?

Well, I got this from the photo.net archives:

Quoting Frances Shultz in November 1998 issue of Shutterbug:

"...ISO film speeds are determined according to the amount of light which is required to give a fixed density (0.10 above film base plus fog) at a fixed contrast (effectively a G-bar or C.I. of 0.615).."

So he thought the ISO speed point WAS 0.1 over b+f. I guess the only way to know for sure is to get hold of a copy of the ISO standard.

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