Operation Manual

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Web graphics
Last updated 9/13/2015
Optimize as GIF or PNG-8 format
GIF is the standard format for compressing images with large areas of solid colors and crisp details like those in line art,
logos, or type. Like the GIF format, PNG-8 supports transparency and efficiently compresses areas of solid color while
preserving sharp detail; however, not all web browsers can display PNG-8 files.
1 Open an image and choose File > Save For Web.
2 Choose GIF or PNG-8 from the optimization format menu.
3 To display an image at low resolution while the full-resolution image is downloading, select Interlaced. Interlacing
can make downloading time seem shorter and gives viewers feedback that downloading is in progress.
4 Under the optimization format menu, choose a color-reduction algorithm for generating the color lookup table:
Perceptual Creates a custom color table by giving priority to colors for which the human eye has greater sensitivity.
Selective Creates a color table similar to the Perceptual color table, but favoring broad areas of color and the
preservation of web colors. This color table usually produces images with the greatest color integrity. (Selective is
the default choice.)
Adaptive Creates a custom color table by sampling colors from the spectrum appearing most commonly in the
image. For example, an image with only shades of green and blue produces a color table made primarily of greens
and blues. Most images concentrate colors in particular areas of the spectrum.
Restrictive (Web) Uses the standard, 216-color, web-safe color table common to the 8-bit (256-color) panels of
Windows and Mac OS. This option ensures that no browser dither is applied to colors when the image is displayed
using 8-bit color. If your image has fewer than 216 colors, unused colors are removed from the table.
5 To specify the maximum number of colors in the color panel, select a number from the Colors menu, enter a value
in the text box, or click the arrows to change the number of colors. If the image contains fewer colors than the panel,
the color table reflects the smaller number of colors in the image.
6 If you chose Restrictive (Web) for the color-reduction algorithm, you can choose Auto from the Colors menu.
Choose Auto if you want Photoshop Elements to determine the optimal number of colors in the color table based
on the frequency of colors in the image.
7 Choose a dithering percentage, either by entering a percentage in the Dither text box or by clicking the Dither menu
arrow and dragging the slider that appears.
8 If the image contains transparency, select Transparency to preserve transparent pixels; deselect Transparency to fill
fully and partially transparent pixels with the matte color.
9 To create an animated GIF, select Animate.
10 To save your optimized image, click OK. In the Save Optimized As dialog box, type a filename, and click Save.