Nikon D90 User Manual page 118

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3
Press
®.
Press
®
to save settings and return to the shooting menu. If
white balance has been fine-tuned on the A-B axis, a
~~
icon
will be displayed in the control panel.
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II The WB Button
At settings other than
13
(Choose color temp.)
and
PRE (Preset manual),
the
WB
button can be used to fine-tune white balance on the amber (A)-blue (B) axis (pg. 97;
to fine-tune white balance when
13
or
PRE
is selected, use the shooting menu as
described on page 97). Six settings in both directions are available; each increment
is equivalent to about 5 mired (see below). Press the
WB
button and rotate the sub-
command dial until the desired value is displayed in the control panel. Rotating the
sub-command dial to the left increases the amount of amber (A). Rotating the sub-
command dial to the right increases the amount of blue (B). At settings other than 0,
a
~~
icon appears in the control panel.
WB button Sub-command dial Control panel
98
• "Mired"
Any given change in color temperature produces a greater difference in color at low color
temperatures than it would at higher color temperatures. For example, a change of 1000 K
produces a much greater change in color at 3000 K than at 6000 K. Mired, calculated by
multiplying the inverse of the color temperature by 10
6 ,
is a measure of color temperature that
takes such variation into account, and as such is the unit used in color-temperature
compensation filters. E.g.:
• 4000 K-3000 K (a difference of 1000 K)=83 mired
• 7000 K-6000 K (a difference of 1000 K)=24 mired