Tom Rittenhouse wrote:
> One of the problems w sunny-16 is
> that when it was the way to meter
> film speed was rated one stop lower
> than it is today. No they didn't
> improve the film, they just changed
> the rating. The difference is that
> before meters were common the film
> makers had a one-stop safety factor
> in the film speed. That allowed the
> film to be over-exposed one stop, or
> under-exposed two stops and still get
> a printable negative. Modern negative
> film has a wider range than that so
> sunny-16 is usually close enough. If
> you are interested this change took
> place in 1959, we photographers do
> like to keep up to date <f>.
Hi Tom ...
I don't doubt you, but I tend to. Far be it for me to challenge the
veracity of your comments, for I'm far from well-versed in these
matters. However, I am somewhat skeptical, so perhaps you'd care to
expand upon this point a little.
Tell me exactly how the film rating was changed. Was it arbitrary?
Did it take into account the film's latitude? Is this true for color
negative film as well as B&W negative? If the actual film speed is
the same, then what you're saying is that film makers are just making
their emulsions faster by rating the film at a higher point within
it's latitude. However, if the film speed is the same, then there's
still only one "correct" exposure in order to garner the best results
from the negative, and that would be the old speed rating, since, as
you say, it's not been changed.
Further, today there are very few emulsions that were available back
when this change was supposed to have occurred, and, of those that are
using the same name have been "improved" (i.e., changed) many times
over. How would you use then "sunny 16" rule with a new emulsion, one
that hasn't had its speed rating modified?
Finally, you mention that this change took place in 1959, and you also
noted that "The difference is that before meters were common the film
makers had a one-stop safety factor in the film speed." These
statements seem somewhat at odds with one another, since meters were
quite common before 1959 and TTL meters didn't appear until after
1959, with some possible exceptions.
So, perhaps you can explain this concept a little more for, being the
mental midget that I am, I'm having a hard time fully understanding
the concept.
--
Shel Belinkoff
mailto:[EMAIL PROTECTED]
"Why should I use a meter? What if the darn thing broke on me
when I was out making a photograph? Then what would I do?"
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