On Mon, 06 Dec 2004 23:03:40 -0800, (Ron
Wong) wrote:

http://www.luminous-landscape.com/tu...stograms.shtml

I've read that article and quite a few others. None mention the
logarithmic distribution and from what I was recently told,
understanding the difference between a log scale and a linear scale is
very helpful in using histograms. He was saying that the histogram of
a properly exposed black-and-white checkerboard (exactly same amount
of blacks and whites) would not show a symmetrical curve. The curve
would be weighted toward the dark end of the scale. A useful thing to
know, apparently. Not that being unaware of that means a person can't
use a histogram to improve exposure.