If you look back, you'll see that I was speaking of spot metering. on
faces when a performer is illuminated by a narrow spotlight. Since the
dumb reflective meter thinks everything is neutral gray, a white face
will be underexposed and a very dark face will be overexposed. You can
get away with the overexposed dark skin -- and sometimes it's preferred
-- particularly when shooting negative film. But the underexposed white
face will read poorly. So you simply add a stop to the spotmeter
reading. An old trick of us older folk is to use an open hand as a gray
card in heavily backlit situations or other difficult metering tasks.
Again, if you're pale white like me, you have to add one stop to the
reading.
Paul
On Aug 1, 2005, at 11:20 PM, Godfrey DiGiorgi wrote:
On Aug 1, 2005, at 7:56 PM, Scott Loveless wrote:
I have what may seem like a dumb question, Paul: why would I want to
overexpose by a stop on light-skinned people but not darker-skinned
people?
Or did I read that backwards?
If their skin comes into play when metering, your camera could
underexpose light skin and overexpose dark skin. So you need to
compensate. But I've always thought this was more a black and white
technique. Does it really apply for digital imaging?
It's a principle driven by basic reflective meter response
calibration. Remember that a reflected light meter believes that
ANYTHING in front of it is an 18% gray average target. Makes no
difference whether you're metering for a sensor or a piece of film,
b&w or color.
Of course, some adjustment to how much you alter the exposure based
upon what the particular film/sensor response curve happens to be is
appropriate...
Godfrey
