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Re: [OM] I was wrong

Subject: Re: [OM] I was wrong
From: Ken Norton <ken@xxxxxxxxxxx>
Date: Thu, 14 May 2009 09:36:56 -0500
>
> I find it interesting that you have such an aversion for Provia,
> though. I am really a fan of Provia, though I do admit I've never shot it
> in
> 35mm, so I've probably never even picked up any meaningful resolution
> difference
> between it an Velvia 100 which I also shoot from time to time.
>


Both Velvia and Provia suffer from lateral halation issues (as opposed to
halitosis issues) which affect edge detail--but I believe the "F" versions
are worse than the non-F. The original Provia 100 and the Fuji 100
predecesor was pretty good stuff. However, if you look at the MTF curve that
Fuji has published for their films, you will see that Provia is down to
around 30% at 50 cycles/mm which is close to its threshold. A 70% response
is approximately 25 cycles/mm.

http://www.fujifilm.com/products/professional_films/pdf/provia_100f_datasheet.pdf

Velvia 100, on the other hand, (not talking 50 or 100F, but specifically
100) the 70% response is a touch better than Provia's 25 cycles/mm. However,
it is only down to 50% at 50 cycles/mm and the threshold is 25% at 100
cycles/mm. This results in a noticable 'crispness' with Velvia over Provia
in the specific frequencies where digital seems to rule the day. The digital
vs. Provia comparisons were always wrong because we photographers thought
that Provia was the sharpest tack in the drawer when it was really no where
close.

http://www.fujifilm.com/products/professional_films/pdf/velvia_100_datasheet.pdf

Fuji 160S is an interesting bird. It's curves show that it's still at a 70%
response at 50 cycles/mm and 50% at 50 cycles/mm. Beyond this point,
however, the curve drops off very quickly and doesn't quite meet 100
cycles/mm. This translates into an almost identical type of response curve
to digital where the response curve is relatively flat farther along than
most films then it hits a brick wall. But up to that brick wall it appears
to be sharper and clearer to the observer.  160S is definitely dye-cloud
limited in the maximum resolution it can offer, but between it's increase in
mid-curve sharpness AND the relative lack of lateral halation make this film
an exceptional performer.

http://www.fujifilm.com/products/professional_films/pdf/pro_160s_datasheet.pdf

BTW, I'm quoting spec sheets here, but these spec sheets definitely hold
true to what I see in my own pictures.

AG
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