Funny you should mention that, Cory. The last time I shot the moon
(400mm lens with two doublers) I used the "Moony 11" rule. Apparently
I did the math wrong, though, because I ended up with a roll of film
that appeared completely unexposed. Not even a hint of a smudge in 24
exposures. I've used the camera and lens since then for other
subjects, so I don't think it was a calibration problem of the
equipment, just one between my ears. :-)
I seem to recall when I did it (300m with two 2x doublers) that I
would figure the "sunny 16" (adjusted for the doublers... f/64 or f/88...
something ridiculous like that) and then grab another 2 or 3 stops. I
find it hard to believe that there's that much loss (doublers were the
cheaper 3? elements, but MC'd at least). I was mostly protesting the
attitude of the poster that seemed to suggest learning about photography
negates the use of a histogram.
One other thing I've noticed about the histogram is that it plots
the JPG-encoded data. That means log-X (so it's linear in stops). Also,
the blown highlight indications aren't completely accurate. If you shoot
RAW, there's often a stop of lattitude more than is indicated by blinky
highlights on the histogram.
-Cory
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* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
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