Viewfinder Grid Display - Nikon D300 User Manual

My Recommendation: If I were using my camera in a quiet
area, why would I want it beeping and disturbing those
around me? I can just imagine me zooming in on that
big grizzly bear, pressing the Shutter-release button, and
listening to the grizzly roar his displeasure at my camera's
beep. I want to live, so I turn off Beep.
You might want the reassurance of hearing the beep when AF
has been confirmed or when the Self-timer is counting down.
If so, turn it on. The AF-assist illuminator flashes during
self-timer operations, so I generally use that instead of the
beep.
This is another of those functions that you either love or hate.
You can have it either way, but be careful around big wild
animals when Beep is enabled. They might think you're
calling them to supper, and you may be the main course.
I don't like my camera beeping at me. As a matter of fact, the
beep sound sets up a harmonic resonance within the bones of
my skull and causes my eyeballs to vibrate. I don't like it!
You may love it. Either way, we can both have our wish.
By the way, Beep is automatically disabled when you're
using the new Q or Quiet-shutter release mode on the
D300S—regardless of how this Custom Setting is configured.

Viewfinder Grid Display

Custom setting d2 (D300S and D300)
(User's Manual – D300S page 275; D300 page 281)
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