Creating the Alpha Channel

It is best to use an alpha channel if you want to obtain an embossed effect using the Lighting effects filter. No need to worry, though: an alpha channel is nothing more than a greyscale image linked to the main image that allows additional information to be stored, such as transparency details for the most part.

Create an alpha channel using your text:

1. Press the Ctrl key (Cmd on the Mac) and click on the type layer, inside the Layers palette.
   
   
A highlighted outline of the text appears in the image.


2. Open the Channels palette by clicking on the tab.
   
   
3. Then on any channel click on the button Save selection. A new channel called Alpha 1 appears.
   
   


Figure 2: Create an alpha channel using your text.

You have created an alpha channel! Yes, that's right. In this channel, your text is white and the rest of the image is black.


4. Choose Select > Deselect. Then click on the Alpha 1 channel in the Channels palette.
   
   
The document window now displays the alpha channel content.


5. Create a white frame around the image in the alpha channel. Press Ctrl/Cmd-A to select the entire image.
   
   
6. Make sure that the foreground colour is white (the default colour), then select Edit > Stroke.
   
   
7. In the Stroke dialog box, select a width of 2 pixels, check the Inside option, then click on OK. Press Ctrl-D (Cmd-D on the Mac) to deselect.
   
   
8. Add a very slight blur to the alpha channel to soften the embossing effect: select Filter > Blur > Gaussian blur, then select a radius of 0.5 pixels.