Unable to adjust mask tracking

[Indie767]

I am somewhat new to AE. I unable to adjust my mask for each keyframe. Selecting the mask shape and moving it also moves the video I'm masking.  Can AE track motion or is a plug-in required?

[Rick Gerard · Accepted solution]

This is a basic skill covered in the Learn section of AE's home screen or the Adobe After Effects product page. Start here: Learn AE

If you are using Mask Tracing you are going to get a new keyframe on every frame so doing a smooth edit is incredibly difficult. You simplify things by actually deleting a bunch of the keyframes and make your adjustment several frames apart so the tweening makes a smoother change to the path.

If you are having problems selecting Mask points you are probably using the selection tool (v) instead of the Pen tool (g). The pen tool + Ctrl/Cmnd or Alt/Option to select the different tools.

Here's a tutorial I did a long time ago that shows you how to edit Bezier paths. Maybe that will help, but you still should spend several hours going through the learning materials in the link I shared.

You can lock the position of a layer by adding an expression to the Position property. That expression is very easy. You can simply type in the same values that you see for "position" by Alt/Option + click on the stopwatch and enter something like this [960, 540] which is the default position for a standard HD layer. Another option for the expression that will work with any layer of any size and keep the Anchor point of the layer precisely in the center of the comp goes like this:

[thisComp.width/2, thisComp.height/2]

[Indie767]

Thanks, I'll check out the tutorial.