(High bit-depth) The three Garbage Matte effects aid in cropping out extraneous portions of a shot so that you can apply and adjust a key effect more effectively. The mattes are applied with either four, eight, or 16 adjustment points for more detailed keying. Once you apply the effect, click the Transform icon  next to the effect name in the Effect Controls panel. This displays the garbage matte handles in the Program Monitor. To adjust the matte, drag the handles in the Program Monitor or drag the controls in the Effect Controls panel.