Adobe 23101335 User Guide - Page 128

Converting to indexed color (Photoshop), Applying colors, Making color and tonal adjustments

Page 128 highlights

118 CHAPTER 3 Working with Color Converting to indexed color (Photoshop) Converting to indexed color reduces the number of colors in the image to at most 256- the standard number of colors supported by the GIF and PNG-8 formats and many multimedia applications. This conversion reduces file size by deleting color information from the image. To convert to indexed color, you must start with either a grayscale or RGB image. To convert a grayscale or RGB image to indexed color: 1 Choose Image > Mode > Indexed Color. Note: The image must be flattened first, or you will lose layers. For grayscale images, the conversion happens automatically. For RGB images, the Indexed Color dialog box appears. 2 Select Preview the Indexed Color dialog box to display a preview of the changes. 3 Specify conversion options. For information on conversion options and customizing indexed color tables, see "Conversion options for indexed-color images (Photoshop)" in online Help. 4 Click OK. Applying colors Once you have set up the color mode for an image, you can specify a foreground and background color by using the eyedropper tool, the Color palette, the Swatches palette, or a color picker. Photoshop uses the foreground color to paint, fill, and stroke selections and the background color to make gradient fills and fill in erased areas of an image. The foreground and background colors are also used by some special-effects filters. For information on specifying foreground and background colors; using the painting, erasing, art history, and gradient tools; and filling and stroking selections and layers, see "Painting" in online Help. For information on filters, see "Applying filters for special effects" in online Help. Making color and tonal adjustments When you photograph, scan, or resample images, you can often introduce problems involving color quality and tonal range. Photoshop provides a comprehensive set of tools for making color and tonal corrections and sharpening the overall focus of an image. ImageReady provides many of the basic correction tools. For more information, see "Making color and tonal adjustments" in online Help.

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CHAPTER 3
118
Working with Color
Converting to indexed color
(Photoshop)
Converting to indexed color reduces the
number of colors in the image to at most 256—
the standard number of colors supported by the
GIF and PNG-8 formats and many multimedia
applications. This conversion reduces file size by
deleting color information from the image.
To convert to indexed color, you must start with
either a grayscale or RGB image.
To convert a grayscale or RGB image to indexed color:
1
Choose Image > Mode > Indexed Color.
Note:
The image must be
attened
rst, or you will
lose layers.
For grayscale images, the conversion happens
automatically. For RGB images, the Indexed Color
dialog box appears.
2
Select Preview the Indexed Color dialog box to
display a preview of the changes.
3
Specify conversion options.
For information on conversion options and
customizing indexed color tables, see
“Conversion options for indexed-color images
(Photoshop)” in online Help.
4
Click OK.
Applying colors
Once you have set up the color mode for an image,
you can specify a foreground and background
color by using the eyedropper tool, the Color
palette, the Swatches palette, or a color picker.
Photoshop uses the foreground color to paint, fill,
and stroke selections and the background color to
make gradient fills and fill in erased areas of an
image. The foreground and background colors are
also used by some special-effects filters.
For information on specifying foreground
and background colors; using the painting,
erasing, art history, and gradient tools; and filling
and stroking selections and layers, see “Painting”
in online Help. For information on filters,
see “Applying filters for special effects” in
online Help.
Making color and tonal
adjustments
When you photograph, scan, or resample images,
you can often introduce problems involving color
quality and tonal range. Photoshop provides a
comprehensive set of tools for making color and
tonal corrections and sharpening the overall focus
of an image. ImageReady provides many of the
basic correction tools.
For more information, see “Making color
and tonal adjustments” in online Help.