On Wed, Aug 19, 2009 at 7:05 AM, Chuck
Norcutt<chucknorcutt@xxxxxxxxxxxxxxxx> wrote:
> One thing I can never recall being discussed is the role of long OTF
> exposure and reciprocity failure. Somehow, I suspect that the 1970s and
> 1980s electronics of the OM system do not compensate for reciprocity
> failure and, even if they did, films vary considerably.
If so, I'm glad they didn't try to compensate, as I recall reading in
one of John Shaw's books that Velvia has negliglble RF, while it is
quite a bit more profound with Kodachrome (soon to be a non-issue).
It should really be up to the photographer to do the compensation. I
recall shooting brackets in the S.Antelope Canyon of exposures which
were approximately in the 30+ second range, or rather I think I just
did one +EC bracket since there wouldn't have been much point in doing
a minus one where RF is involved. It is always good to have the
brackets, but I can't recall that the issue of possible RF ever raised
its ugly head in viewing the resulting slides. That's not a very good
test environment, however, and the exposure measurements in themselves
are tricky. The ability to do a lengthy auto exposure based on a
single spot reading is wonderful in a situation like that (a slot
canyon, I mean). I fell in love with my OM-4T as a result of it.
Joel W.
--
_________________________________________________________________
Options: http://lists.thomasclausen.net/mailman/listinfo/olympus
Archives: http://lists.thomasclausen.net/mailman/private/olympus/
Themed Olympus Photo Exhibition: http://www.tope.nl/
|