On Wed, 8 Sep 2010 19:06:45 UTC, Lew wrote:

You're correct about the palm, however I wasn't necessarily referring
to white skin, nor have I tested black skin. I just used the trial &
error method on my skin and reported the result in my email. You are
correct in inferring that I am of Caucasian origin, however I believe
that anyone of any race or skin color may use this trial & error
method to arrive at an adjustment suitable for their practice as long
as they have hands.
_____
I have used this very same method to measure reflected light (and
inferred incident light) for years. The palm of my left hand reads 1
1/2 stops to 2 stops too high using the built-in camera light meter
(Nikon F2/F3), and i set the camera accordingly. Neutral gray card
stays at home. It does not matter if the incident light is from
direct sun, or cloudy sky.

/ John

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