Nikon D300 User Manual page 302

That's all there is to it! Just remember that you have Fine tune
optimal exposure turned on, since the camera will not remind
you. Watch your histogram to make sure that you're not
regularly underexposing or overexposing images once you
have the fine-tuning adjustment in place. If so, just go back in
and adjust the fine-tuning up or down, or turn it off.
My Recommendation: Fine tune optimal exposure is a
rather controversial setting. However, I find that I have better
pictures when I run the Matrix meter 3/6 (1/2 EV step) over
the normal setting. Why? Well, Matrix metering seems a bit
conservative to me and tends to work hard to keep from
blowing out the highlights in an image. It seems to
underexpose my images by about 1/3 EV step, most of the
time. I am judging this by the fact that on most of my Matrix
meter exposed images, the histogram doesn't quite make it to
the light-side edge of the histogram window, which I prefer. I
like to expose for the highlights, yet my camera always
slightly underexposes. I had exactly the same results from my
original D300, and now also with my newer D300S.
My reaction is simply to increase the exposure just a little and
force the histogram to the right edge. This can be dangerous
because slightly overexposed images tend to blow out all
detail. So I carefully examine the histogram on important
images to make sure it is where I want it to be. When I run
Matrix metering over by 3/6, the histogram is usually right
where I like it.
Remember, please, that this is an experiment for each of us. If
you choose to fine-tune any of the three metering systems,
you should test it well before doing an important shoot. I am
basing my fine-tuning experience on my own imaging style
and results and can't guarantee that you'll get the same good
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