How do you add the first keyframe for your mask path in After Effects?

To add the first keyframe for your mask path in After Effects, you activate the stopwatch icon next to the mask path property in the timeline. This action begins tracking changes to the mask path over time and establishes a keyframe at the current time marker.

When the stopwatch is clicked, After Effects automatically creates a keyframe at the position of the playhead, capturing the current mask path's attributes. This allows you to adjust the path at various points in time, creating an animation that follows changes in the mask shape. As you adjust the mask path later, additional keyframes will be generated similarly, allowing for smooth transitions and complex animations based on changes to the mask.

Other options do not directly initiate the creation of a keyframe for a mask path. Simply double-clicking a mask layer allows you to edit the mask but does not constitute the keyframing process. Selecting add keyframe via a right-click does not apply in this context, as there is no direct command to add a keyframe this way specifically for properties like the mask path. Pressing the K key moves the playhead forward to the next keyframe, rather than creating a keyframe itself. Each of these alternatives lacks the functionality of the stopwatch method, making it clear why