Nikon D300 Complete Manual page 67

Note: Some of the test charts presented in this eBook and on my
Web site are pieces of the elaborate testing results that the
Imatest testing software produces. Imatest is also the
software I use to verify the things I see in D300 images.
While I don't always present the test results in this eBook
(you've got enough pages and examples to wade through as
it is), almost all of my statements about image quality
properties have been empirically tested by both careful
image shooting and running standard test charts through
Imatest.
Imatest is probably the most precise testing facility easily
available to the average user. I highly recommend it as a
way to get to know the nuances of your camera's response.
One small thing, though: you'll need a number of test charts
to take full advantage of the program, and some of these
charts are expensive because they're produced to exacting
standards. See
And don't forget to tell Norman that I sent you.
However, the question on most D300 user's minds isn't 8-bits
versus 14-bits, it's 12-bits versus 14-bits. If you shoot JPEG or
TIFF because you need ready-from-the-camera output, you
have to live with the 8-bitness of your output (though you can
still optimize a few settings to help the camera's processing).
But if you're shooting NEF to get "optimal" data, the question
quickly becomes whether to use 12-bits (which supports the 6
or 8 fps continuous drive the camera is capable of) or 14-bits
(which drops the maximum speed of the camera down to 2.5
fps).
Why does camera speed drop when you shoot with 14-bits
instead of 12-bits? The most likely explanation is this (Nikon
isn't saying): it takes longer to count when you count by one
instead of counting by four. Try it.
Count to 40 by 4's: 0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40 and
done.
Thom Hogan's Complete Guide to the Nikon D300
http://www.imatest.com
V1.02
for more details.
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