Brightness, Contrast, And Color-Balance Palette; An Introduction To Color - Minolta Dimage Scan Software Manual

Brightness, contrast, and color balance palette
Click the brightness, contrast, color-balance
button to display the palette.
Drag the brightness, contrast, or color sliders, or enter
specific values in the corresponding text box to make
corrections. Dragging each slider to the right or inputting
a positive number in the text box increases the
brightness, contrast, and color.
Changes will be reflected in the displayed image and in
the graph at the top of the palette. The horizontal axis of
the chart indicates the original image values and the
vertical axis the new values. Click the reset button to
cancel all changes.
Clicking the auto-setting button corrects the brightness
and contrast automatically without affecting the color
balance. Click the reset button to cancel the changes.
Is this picture too light? Adjusting brightness and contrast
can be more difficult than it looks. The image on the right
looks too bright, especially the mountains in the
background.
Simply making everything darker with the brightness
controls creates a muddy image - the snow and sky are
a dull gray and there are no strong blacks.
By adding contrast to the image, the snow is brightened
while the darker trees are accentuated. The extra
contrast also gives the image the appearance of being
sharper as well as revealing fine details.
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ASIC IMAGE PROCESSING

An introduction to color

In photography, red, green, and blue are
the primary colors. The secondary
colors, cyan, magenta, and yellow, are
made from combining the primary colors:
cyan = blue + green, magenta = blue +
red, and yellow = red + green. The
primary and secondary colors are
grouped in complementary pairs: red and
cyan, green and magenta, and blue and
yellow.
Knowing the complementary colors is very important in color balancing. If the image
has a specific color cast, either subtracting the color or adding its complementary color
will create a natural looking image.
RED
GREEN
BLUE
If the image is too
CYAN
MAGENTA
YELLOW
Adding or subtracting equal parts of red, green, and blue will have no affect on the
color balance. However, it can change the overall image brightness and contrast.
Usually, no more than two color channels are needed to color balance an image.
Color balancing is a skill that develops with practice. While the human eye is extremely
sensitive in making comparative judgements, it is a poor tool when making absolute
measurements of color. Initially, it can be very difficult to distinguish between blue and
cyan, and red and magenta. However, adjusting the wrong color channel never
improves an image; subtracting blue from an image that is too cyan will give a green
cast to the image.
RED
MAGENTA YELLOW
BLUE GREEN
CYAN
Decrease the amount of red.
Decrease the amount of green.
Decrease the amount of blue.
Increase the amount of red.
Increase the amount of green.
Increase the amount of blue.
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