Nikon 25338, User Manual

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Chapter 22
Adjust Menu
THRESHOLD
The Threshold slider is designed to
limit where sharpening is applied with
the current settings. The higher the
threshold setting, the less that objects
in the image will be sharpened. This
slider works to indicate how much of
a difference between one pixel and its
neighbors is necessary in order to apply
sharpening. This slider is helpful in
preventing smooth areas from picking
up noise artifacts, such as when sharp-
ening skin areas or landscapes with
large amounts of sky. Too high a thresh-
old setting will prevent any objects
from being sharpened in the image, so
it is important to find a good balance.
Once you have set the three sliders
within the Unsharp Mask feature, you
can return to the Channel Menu and
select an additional channel to sharpen.
You may also select one of the channels
that you have already applied sharp-
ening to in the Channel Sharpening
List box. After selecting one of the
channels, you can modify those settings
by rearranging the sliders, or you can
delete the effect on that channel by
clicking on the button.
Once you are satisfied with the results
of the Unsharp Mask feature, click on
the OK button. If you want to cancel
the feature, click on the Cancel button.
Correct
Color Aberration Control
The Color Aberration Control feature
can be used to adjust and control
potential color fringes that can occur
in photographs. Color aberration is
caused by the different angles at which
the different color wavelengths are
refracted when traveling through a
lens element. The result, called a color
aberration, appears as a color halo on
the side of an object that is positioned
away from the center of the image.
The controls provided within the Color
Aberration Control feature help remove
the color fringing by providing you with
two sliders that shift colors into and
away from the center of the image. It is
recommended that you view the image
at 100% while making color aberra-
tion changes. It is important to review
the results of the changes, especially
around the corners of the image, to
balance the effect.
RED — CYAN
The Red — Cyan Slider contracts and
expands the red channel to reduce
either red or cyan fringing. Moving the
slider to the left reduces red fringes,
while moving the slider to the right