JimKramer <jimG@[EMAIL PROTECTED]
> wrote:
>
> Looking at the XP2 and the BW400CB, I can't help but wonder how they
> would compare at the same exposed ISO?
You mean if XP2 were (under)exposed at 400? Would resolution decrease?
It's not clear to me whether usable stops and resolution are measured
at the box-speed rating, or at the actual film ISO.
> I think the table is being generous with Velvia100F.
That's probably a discontinued film now, or nearly so, but unfortunately
the Russian institute didn't test new Velvia 100.
Do you think they're being generous with
> What is ProPhoto400BW?
I'm not certain, but I believe it's similar to discontinued Portra 400BW.
> Was there an explanation of rational behind the "wild" ISO testing,
> some over, some under?
Yes-- most films are not accurately rated. There are various categories
expected in certain markets, and depending on what the chemistry yields,
manufacturers provide product in these categories. The most infamous
example was old NPH, which was really a 200 speed film. A less famous
example is Kodak 100UC, which is faster than 100 speed, and probably
very similar (or the same) as Elitecolor 200 in Europe. New Portra 800
seems faster than 800 to me. That's one of the films that was revised
since this testing. Others are the new Portra 160/400s just appearing.
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