# Using channels for special effects

When you save source art as a 3DO cel, you can use additional channels in Photoshop for certain special effects that the 3DO hardware can create. This chapter gives step-by-step examples for creating irregularly shaped cels and for using special effects. Here's an overview of what you can do:

- Create an irregularly shaped cel by first creating a mask that indicates the region you want transparent. Then assign the channel of that mask to the Transparency channel of the cel.

- Make parts of your cel bright or translucent by specifying those parts in a mask. If the cel type permits, you can use one mask for transparency, the other mask to indicate the special effects region.

- Enhance the red, green, or blue channel to highlight that color only, copy that channel into a separate channel and save it as a mask with a special pixel mode.

- Make the whole cel translucent or dark for ghost or shadow effects.

Note: For more information, see "Introduction to 3DO Graphics" in this volume.

## Which channels can I use?

The cel type and the number of bits per pixel determine whether additional channels are available for a given cel. The CelWriter dialog makes certain options unavailable for certain cel types. If a channel does not make sense for a certain kind of cel, it is dimmed in the dialog.