[Konvas] "Overexposing" via meter

[Rick Garbutt]

All of Prof Stone's comments are bang on the money - and he saved me typing
out the Sunny-16 Rule story.

Second--  As for the black and white film?  The temp would float off the
emulsion, even if it was Rodinal at 100F-- the black and white emulsion just
won't handle the temp.  The lab guy should have been flogged, but one time I
watched friend of mine talking to someone else just do fixer first, then
stop, then developer-- and then stared at the film trying to figure out what
was wrong.  The colored trays in the wrong order kind of gave it away, but
he never lived it down.  Stupid happens.

Note also that, even if the emulsion had withstood the relatively hot
developer, as soon as the film hit the ferricyanide bleach, all that
developed silver would have been rebrominated, and the entire image would
disappear forever in the fixer.  In color, you only get to "borrow" the
silver - ALL of it (except if you're making release prints with silver or
silver sulphide sound tracks) is removed, leaving only dye clouds making up
the final image.  Unless, of course, you're doing some wing-ding bleach
bypass process, in which case some silver would remain with the dyes.  But
soundtracks and BBP are special cases.

I, too, once had a lab gaily process several rolls of 5222 (Double-X B&W) as
color negative.  All very clearly labelled, and bearing my note to the
show's Production Manager these would have to go to another lab, as the one
we were using didn't handle B&W at all.

Stupid 1:  PM ignored my note, and sent the B&W film to the lab not equipped
to handle it.
Stupid 2:  The lab, despite clear labelling, ran the B&W film as though it
was color.

Result:  the film came back as clear grey plastic - even the edge numbers
had vanished.  I do so love it when other people know my job so much better
than I do...

Remember the World War II acronym, SNAFU - Situation Normal, All F****d Up?
Experiences like mine have led (got this one from the military, too) to
another acronym, which I really like:  TASFURIA, which you can pronounce,
like SNAFU, as though it was a real word.  This one expands to Things Are So
F****d Up It's Really Amazing.  And when stupidity compounds on stupidity,
we arrive at TASFURIA.

And stupid does happen, and it can happen to anybody.  Hence the requirement
for constant vigilance.

Third--- and the real meat of this reply--  "proper exposure" is a hoax.
Nominal exposure reproduction is the basis for what we CALL proper exposure,
but it does not really exist.

<snip!>

All film exposures are approximate depending on a number of factors.  The
same amount of light falling on the same object using the same film may vary
based on the color of the light and/or the color of the object--  a light
green ball with 100 lux of "mixed mid day daylight" on it will not be the
same as it is with 100 lux of 3200k light on it.

Only now, in some data sheets, Kodak gets all Scientific about it, and talks
in general terms about things like "a nominal density of 1.0 above base fog,
achieved by impingement onto the emulsion of light intensity of <some
number> of ergs/square centimeter of emulsion..."  But it's still really
grounded in that old grey plank.

All exposure is nominal and approximate.

Overexposure of a negative by a chosen amount is a habit of most older
photographers-- and based on the film, time of day, objects, et cetera, it
varies.

As Kodak points out (publication H-1, which I've recommended before) all
exposure recommendations are to be considered STARTING PONTS ONLY.  As HW
has pointed out, all the above factors enter into it, as well as details of
exactly how your lab agitates during processing, the repeatable purity of
the chemicals they mix, whether they're trying to scrimp on vital things
like the color developing agent or running rather lower replenishment rates
than they should, and your own personal metering technique.

Until you start taking detailed sensitometric density readings of
standardized subjects (grey card and grey scale, for instance)
"overexposure" is a kind of relative term.  Will the neg print to a good
print?  If yes, then the exposure is right.  But even "right" can be
relative.

There was an American Cinematographer article years ago about filming
Disney's The Ugly Dachshund.  Interviewer commented to the DoP that he was
"using an awful lot of lights for the night exteriors."  The reply was "yup,
because a good, dense negative will give you better-looking prints, and more
of them!"  He's dead right, and I've always carried that nugget of
information with me.  And my blacks are BLACK, and my colors pop on
projection.  You can always dull 'em down, but yanking 'em up always looks
cheesy.

For still color negative I almost always tried to go from one third to one
and a half over, and never had a problem.  Of course, a lot of the "how
much" had to do with a few decades of doing it, too, but overexposure of
color neg stock never gave me a problem-- and almost always solved many that
could have occured.  Black and White negative needed to be one quarter to
one half stop over, not more, and color reversal needed to be UNDER by a
half stop or so.  Black and white reversal was usually best "dead on" or a
quarter stop under to make the image "pop" when projected.

Exactly my experience and practice.  And this, incidentally, shows how
negative film benefits from having more "head room" on its sensitometric
curve.  Meaning it can tolerate startling overexposure before all hope is
lost.  With digital, once that pixel is white, the only way it'll ever be
anything else is if you paint something over it.

What you want is 80% nominal reproduction of a forty five degree 18% gray
fifty percent reflectance board during mid day of a clear day during the
month of July in Rochester, NY.

Good luck on that one.

Aaaaaaaaaa-men!

Very (see previous salutation) best again,
Rick Garbutt, soc

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