Adobe 13102498 - Photoshop CS3 - Mac User Manual page 409

Use the Texture Channel in the Lighting Effects
The Texture Channel in the Lighting Effects dialog box lets you control lighting effects using grayscale images (called
bump maps) that you add to your image as alpha channels. You can add any grayscale image to your image as an alpha
channel, or create a new alpha channel and add texture to it. For an embossed text effect, use a channel with white
text on a black background, or vice versa.
1 If necessary, add an alpha channel to your image. Do one of the following:
• To use a texture based on another image (for example, fabric or water), convert that image to grayscale, then drag
the grayscale channel from that image into the current image.
• Drag an existing alpha channel from another image into the current image.
• Create an alpha channel in your image, then add texture to it.
In the Lighting Effects dialog box, choose a channel from the Texture Channel menu: either an alpha channel
2
you've added or the image's Red, Green, or Blue channel.
Select White Is High to raise the white parts of the channel from the surface. Deselect this option to raise the dark
3
parts.
Drag the Height slider to vary the texture from Flat (0) to Mountainous (100).
4
See also
"Create and edit alpha channel masks" on page 272
PHOTOSHOP CS3 402
User Guide