Nikon 25338, Руководство пользователя

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Chapter 22
Adjust Menu
within the Levels & Curves editor.
You can begin to modify the lightness
of your image either by moving the
Black, White, and Mid Point Sliders or
by editing the Curve directly.
BLACK, WHITE, AND
MID-POINT SLIDERS
The Black, White, and Mid Point Sliders
will
automatically adjust the Curve for you.
Black Point Slider
Move the Black Point Slider to the right
to set all luminosity values from the
point you have selected and to the left
to complete black (or to the absence of
the channel’s color when working on an
individual color channel), while redis-
tributing all of the values to stretch the
luminosity range to match the entire
possible range of values. It is recom-
mended that you move the Black Point
Slider all the way to the right to match
up with the left-most information from
the displayed histogram. This adjusts
the current image so that the darkest
values in the image match the darkest
value that can be displayed in a digital
file.
White Point Slider
Move the White Point Slider to the left
to set all luminosity values from the
point you have selected and to the right
to complete white (or to the maximum
lightness of the channel’s color when
working on an individual color channel),
while redistributing all of the values to
stretch the luminosity range to match
the entire possible range of values. It is
recommended that you move the White
Point Slider all the way to the left to
match up with the right-most informa-
tion from the displayed histogram. This
adjusts the current image so that the
lightest values in the image match the
lightest value that can be displayed in a
digital file.
Mid Point Slider
Move the Mid Point Slider either to the
left or to the right in order to lighten or
darken the mid-tones of the image.
You may also click directly on the Curve
to add an anchor point that can be
moved and adjusted. By increasing the
slope of the Curve you will increase
the contrast in the image. Decreasing
the slope of the Curve will decrease
the contrast in the image. The anchor
points may also be set to minimize the
amount of change that occurs to a
tonal range of the image.
Anchor points can be removed by
simply clicking and dragging the anchor
point outside of the Histogram.
The Levels & Curves editor provides you
with a number of additional controls:
BLACK AND WHITE
OUTPUT SLIDERS
These two sliders enable you to set the
maximum and minimum brightness
levels of the image. By dragging the
Black Output slider up, you lighten the
darkest luminosity level in the image,
and by dragging the white output