1. Duplicate object or layer in used image editor
2. Trigger Knockout
3. Zoom to a comfortable view.
4. Select inside object mask tool. Option polygon and plus enable. After
first click hold Alt key. It let you draw freely if required. Use negative
option to subtract if necessary.
5. Click Auto outside mask button.
6. Select outside mask tool same options as inside. Touch up outside mask.
7. Other operations if necessary.
8. Process Knockout. If isn't perfect don't worry about it.
9. Inside image editor create a mask for Knockout object/layer.
10. In original layer or object create a Clip Mask form Mask. Delete
Knockout object/layer. Paint using a brush with white or black to touchup
mask. Apply Clip Mask when you are satisfied.
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Michael Cervantes
C-Tech Volunteer