Adobe PHOTOSHOP 5.0 User Manual page 328

320 CHAPTER 14
Saving and Exporting Images
To export an indexed-color image to GIF:
To define background transparency using a
1
mask, select the area of the image you want to
remain visible. Then click the Save Selection
button (
to create an alpha channel based on your selection.
Choose File > Export > GIF89a Export.
2
If you created an alpha channel in step 1, choose
3
the channel name for Transparency From. Hold
down Alt (Windows) or Option (Mac OS) as you
choose the channel name to reverse the mask
contents. Skip to step 5.
If you did not create an alpha channel in step 1,
4
assign transparency to desired colors in the image:
To add to the background transparency, click the
•
eyedropper-plus tool ( ), and click the desired
areas in the preview or the desired swatches. The
selected colors appear highlighted in the swatches.
To remove a colored area from the background
•
transparency, Alt-click (Windows) or Option-
click (Mac OS) the eyedropper-plus tool to toggle
to the eyedropper-minus tool. Click the desired
color swatch.
To remove all areas from the background trans-
•
parency, hold down Alt (Windows) or Option
(Mac OS), and click Reset.
) at the bottom of the Channels palette
To navigate the image preview, follow the guide-
•
lines described in step 5 of "Exporting RGB images
to GIF" on page 317.
To activate the eyedropper-minus tool
while the eyedropper-plus tool is selected,
press Ctrl (Windows) or Command (Mac OS).
To activate the eyedropper-plus tool while the
eyedropper-minus tool is selected, press Shift.
Do one of the following:
5
To preview the background transparency as the
•
gray background color used by many Web
browsers, leave the Transparency Index Color box
at the default color.
To preview the background transparency as a
•
different color, click the Transparency Index Color
box. Specify a color, as described in "Using the
Adobe Photoshop Color Picker" on page 218, and
click OK.
Note: The Transparency Index Color is used only to
preview the background transparency, and does not
affect the final appearance of the file.
6 Specify Interlaced and Export Caption options,
as described in steps 7 and 8 of "Exporting RGB
images to GIF."
7 Click OK to export the file. Choose a location
for the exported file, and click Save.