Actually the alpha channel is something else entirely... An alpha channel is a specific 8-bit-portion of your image that defines TRANSPARENCY. Think of it as an extra grey-scale image tacked onto your original that defines what areas are transperent and which are opaque. In fact that is exactly what it is, and it turns a 24-bit image into a 32-bit image because of the extra 8-bits of transparency data. (Hope I didn't get too nerdy there...just rying to help.)