On Wed, 25 Nov 1998 12:51:50 -0500, frogsong@ibm.net wrote:

>I took some slides awhile back and have a question about some over
>exposures that I got on some of them. I was using a Nikon 6006 in
>program mode. The situation was that we were in the 5 ponds wilderness
>in upstate NY and were in an area of severe blow down (just about 100%
>distruction of old growth forest by a wind storm ... very sad). We were
>in bright sun light surrounded by hundreds of acres of downed trees that
>were bouncing light around all over the place. It was very bright. I
>tried to take some pictures of the devestation with a companion in the
>middle foreground for scale, interest etc. Now from what I understand
>about the 18% grey assumption, the computer making these shots should
>have UNDERexposed the pictures ... as the silvery tree bark was
>reflecting alot of light. So what was going on? Any thoughts? (maybe,
>despite the intense light, the trees were really reflecting less light?
>or what).
>The other slides in the role were ok ...composition not withstanding
>:-)

The problem with trying to rely on "roll-'o'-th'-dice" metering is
that it doesn't give you much of a basis for making corrections...
If you used center-weighted metering, you could then (almost...!)
make observations about the subject tones/lighting, and make
intelligent corrections. The problem is that many newer cameras
have non-linearities built into their basic meters that make straight
readings in bright light also difficult to rely on (they "correct" a
very bright reading so as not to underexpose beach and snow scenes,
but they can then overexpose other things...). Yuck!!! The more camera
metering enters the "twilight-zone" to aid people without knowledge
about basic exposure technique, the more that metering makes it
difficult for the more knowledgeable to meter accurately...!
(I think you are discovering this...;-)