Graphics Programs Reference
In-Depth Information
Working with alpha channels
When an image has a background that isn't solid white or black, Detect Edges may not
be able to remove the background effectively. With such images, hiding the background's
lightness values may also hide parts of the subject that use the same lightness values. In-
stead, you can use the advanced background-removal tools in Photoshop to specify trans-
parent areas usingpathsoralpha channels, andthenlet InDesignmake aclipping pathfrom
the path or alpha channel.
Note
If you place a Photoshop (.psd) file that consists of an image with a trans-
parent background, InDesign keeps the transparency without relying on
clipping paths or alpha channels. A transparent background can be espe-
cially helpful when you place an image with a soft or feathered edge.
Importing a Photoshop file with alpha channels
You imported the previous image using the Place command. This time, you will use an al-
ternate method: dragging a Photoshop image directly onto an InDesign spread. InDesign
can use Photoshop paths and alpha channels directly—you don't need to save the Pho-
toshop file in a different file format.
1.
In the Layers panel, make sure that the Photos layer is selected so that the image is
placed on that layer.
2.
Navigate to page 2 of your document, and choose View > Fit Page In Window.
3.
Switch to Explorer (Windows) or the Finder (Mac OS), and open the Lesson10
folder, which contains the 10_d.psd file.
Resize and arrange your Explorer window (Windows) or Finder window (Mac OS)
and your InDesign window, as needed, so that you can simultaneously see the list
of files in the Lesson10 folder and the InDesign document window. Make sure that
the lower-left quarter of page 2 in your document is visible.
Note
When you place the file in step 4, be careful to drop it on the pasteboard
area to the left of page 2. If you drop it on a preexisting frame, it is placed
inside the frame. If this happens, choose Edit > Undo, and try again.
