"what you are trying to accomplish when you rate stock at a lower iso"
Hi Jesse,
you would "rate" (I would prefer the term "treat") a film at a different speed
in order to change it's latidude, it's colour rendition, it's contrast a.s.o.
I once had to do a shot of a huge garage two levels under the surface and lit by
a shaft of sunlight coming in in the middle. For the eye it was still "okay" but the meter saw 17 (!) stops
difference between the spot where that light hit and the lowest part I wanted to have
definition on in the picture. I used ILFORD FP4 125 ASA 4x5" black & white sheet film and
the film "properly" treated at it's original rating would have never been able to either not
burn out whites or dump the blacks so I overexposed it treating it as 25 ASA and slowing
him down again in the lab (minus two stops). I wasn't so sure it was going to work at all,
but I had recently read ANSEL ADAMS "The Negative" (wich is a book I will highly recommend
for you to read as well) and wanted to apply the "zone system" created by him and explained very,
very well in his book.
In fact when I came to the pick up my negs the lab guys gathered around me
showing me the print they had already made (without me ordering it) because they said it
was the most beautiful neagtive they had ever seen... (this paid me for the initial moment of
anxiety when first (me asking to "pull" two stops) looked at me with that look saying "why can't you just
do as you are told by the package and the meter"...
The negative has in fact a very "uncommon" look but this is not your final result, it's just a step towards
a print, that of course needs to compensate for that "lacks" of the negative but then brings you all the detail
you were looking for in the first place.
I'm serious, Ansel Adams book(s) are about the best you can ever read to clearly understand exposure
and make very clear for you what it is you are looking for in a negative.
Best of luck and gretings,
Phil
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Phil Soheili
corporate portrait photographer
images of Italy
+49 172 7489874
Edelweiss Strasse 10
81541 Muenchen
Deutschland (Germany)
europhoto.us
phil@europhoto.us