How to mask in After Effects

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Here’s a step-by-step tutorial on how to mask in After Effects:

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1. Select the 'Pen Tool' from the toolbar
2. Make sure no layer is selected and start tracing the mask you want to draw
3. Press 'T' to open the opacity slider and adjust if the mask is interfering while tracing
4. Once done, use the same slider to adjust the opacity back to 100%
5. Select 'Track Matte' dropdown on the layer you want to mask
6. Select the layer containing the mask you have drawn
7. Use the 'Invert' switch to reverse the masked area
8. This should get you to the desired output

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