How to Format Using the Alpha Channel

Adobe Photoshop images can be formatted by selecting the "Alpha Channel" from the "Channels" tab of the "Layers" menu. Once you select the alpha channel for a particular layer of your image, you can open an additional menu where you specify how the alpha channel will be used to format the image. Formatting occurs by using the brush tool to paint areas that will be specified as a "Masked" area or as a "Selected" area.

Instructions

1. • 1
     Launch Adobe Photoshop CS5. Click "File" at the top of the window, click "Open," and double-click the file containing the alpha channel with which you want to format your image.
   • 2
     Click the layer containing the alpha channel from the "Layers" menu at the right side of the window. If the "Layers" menu is not visible, press "F7."
   • 3
     Click the "Channels" tab at the top of the "Layers" menu, and double-click the "Alpha" channel to open the "Channel Options" pop-up window.
   • 4
     Format your image by selecting the "Masked Areas," "Selected Areas" or "Spot Color" option at the center of the pop-up window, then click "OK." When the "Masked Areas" option is selected, you can use a black paint brush to increase the masked area of your image, or you can use a white paint brush to increase the selected area of your image. The "Selected Areas" option reverses this setting, while the "Spot Color" option converts an existing alpha channel to a different color channel of your choosing.
   • 5
     Click the "Brush Tool" from the toolbox at the left side of the window. Click the "Set Foreground Color" square at the bottom of the toolbox, and select a black or white color, depending upon how you wish to format your image.
   • 6
     Draw on your canvas with the brush tool to specify the masked and selected areas of the image.