How to Mask with alpha channels in Adobe Photoshop CS4 or CS5
Much can be said of masking: Masking is the art of using the image to select itself. Masking lets you apply the entire weight of Photoshop to the task of editing a selection. And masking, thy name is alpha channel. Whether you're new to Adobe's popular raster graphics editing software or a seasoned professional just looking to better acquaint yourself with the program and its various features and filters, you're sure to be well served by this video tutorial. For more information, including detailed, step-by-step instructions, watch this free video guide.