Viewfinder Warning Display - Nikon D300 User Manual

4. Press the OK button to lock in the setting.
My Recommendation: I use these grid lines to line up
things as I shoot so that I won't have weird tilted horizons and
such. Many of us tend to tilt the camera one way or another,
and grid lines help us see that we've tilted the frame.
I especially enjoy shooting with grid lines enabled when I'm
down at the beach. Who needs tilted ocean views? When
shooting architecture, the grid lines are invaluable for making
sure buildings, walls, and doors are correctly oriented. There
are lots of ways to use the Viewfinder grid display.
If you set Viewfinder grid display to On, I doubt that you'll
turn it back Off. The nice thing is that you can turn the grid
lines On and Off at will. You don't have to buy an expensive
viewfinder replacement screen for those times you need grid
lines.

Viewfinder Warning Display

Custom setting d3 (D300S and D300)
(User's Manual – D300S page 275; D300 page 282)
Viewfinder warning display puts a low-battery warning in the
Viewfinder, so we'll know when our camera's battery is
getting low on power.
Figure 4-33 shows the location for the Viewfinder warning
display in the Viewfinder (see red arrow). It only appears
when the battery gets down to one notch left.
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