Adobe photoshop elements Benutzerhandbuch
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ADOBE PHOTOSHOP ELEMENTS
User Guide
surrounding pixels and diffused throughout the
image, resulting in a grainy, filmlike texture. This
option is useful for viewing images on a black-
and-white screen.
image, resulting in a grainy, filmlike texture. This
option is useful for viewing images on a black-
and-white screen.
Original grayscale image, and 50% Threshold
conversion method
conversion method
Pattern Dither conversion method, and Diffusion Dither
conversion method
conversion method
To convert a Bitmap-mode image to grayscale:
1
Choose Image > Mode > Grayscale.
2
Enter a value between 1 and 16 for the size ratio.
The size ratio is the factor for scaling down the
image. For example, to reduce a grayscale image by
50%, enter 2 for the size ratio. If you enter a
number greater than 1, the program averages
multiple pixels in the Bitmap-mode image to
produce a single pixel in the grayscale image. This
process lets you generate multiple shades of gray
from an image scanned on a 1-bit scanner.
image. For example, to reduce a grayscale image by
50%, enter 2 for the size ratio. If you enter a
number greater than 1, the program averages
multiple pixels in the Bitmap-mode image to
produce a single pixel in the grayscale image. This
process lets you generate multiple shades of gray
from an image scanned on a 1-bit scanner.
Converting to indexed color
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 Web browsers.
This conversion reduces file size by deleting color
information from the image.
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 Web browsers.
This conversion reduces file size by deleting color
information from the image.
Note: To convert to indexed color, you must start
with either a grayscale or RGB image.
with either a grayscale or RGB image.
To convert an image to indexed color:
1
Choose Image > Mode > Indexed Color.
2
Click OK to flatten layers.
Note: This will flatten all visible layers and discard
hidden layers.
hidden layers.
For grayscale images, the conversion happens
automatically. For RGB images, the Indexed Color
dialog box appears.
automatically. For RGB images, the Indexed Color
dialog box appears.
3
Select Preview the Indexed Color dialog box to
display a preview of the changes.
4
Specify conversion options as described in the
following sections.
5
Click OK.
Palette types for indexed-color images
A number of palette types are available for
converting an image to indexed color.
converting an image to indexed color.
Exact
Creates a palette using the exact colors
appearing in the RGB image—an option available
only if the image uses 256 or fewer colors. Because
the image’s palette contains all colors in the image,
there is no dithering.
only if the image uses 256 or fewer colors. Because
the image’s palette contains all colors in the image,
there is no dithering.