If you move a layer that has a mask applied to it, it will move the entire layer including the mask. But if you wanted to move the image or whatever's being masked but keep the mask in place use the pan behind tool which is up here or it's also y on the keyboard so you can just slide the image like this.
I really wish I found your channel sooner! thank you so much for making some in depth tutorials explaining properly effects, what you're clicking on, and explaining why different methods may work as well as suggestions for how to use these in actual projects. These are the best tutorials I have seen so far and I fully intend to binge your channel and try things out! Thank you for clearly explaining the Adobe programs as well and how they work together - adobe can be overly complicated and you make it super easy to learn :)
Is there a way to feather the mask from the inside of the shape and stop at the outside line? Like can I make the center of a circle 100% transparent, but then cut it to zero transparency at the very line of the circle?
Yes! First create a mask that's a circle and check the 'Inverted' checkbox. Adjust the Mask Feather amount. To make the feathering stop at the outside edge of the circle, create another circle mask on the same layer. An easy way to do this is to duplicate (command or control D) the first mask. Make sure the second mask is below the first. Set the feather on the second mask to be 0. I hope I understood correctly and this is the look you're trying to achieve!
If you have a mask on a native After Effects shape layer (NOT an image, video, or layer imported from Illustrator), you can scale the shape without scaling the mask. To do this, toggle open the shape layer, under Contents > Shape (like Rectangle, Ellipse, etc.) 1 then under Transform: Shape 1, adjust this scale value. If your mask isn't on a shape layer, there's not a simple way to scale the layer without scaling the mask. It might be better to use Track Mattes which I cover in this video: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-UCtM-0Q28cs.htmlsi=aubSqO-yPNsRmH0E Hope that helps!
If you toggle open the layer, under Mask -> Mask 1, you can animate the Mask Path, Mask Feather, Mask Opacity, and Mask Expansion. If you were hoping to animate transform properties like position, scale, and rotation, you might be better off using a matte. Here's a video on mattes: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-UCtM-0Q28cs.htmlsi=nn79iiCYY7HOo2iO
You're right, there's no position, rotation, or scale for the mask. You might be better off using a matte instead of a mask if you need those properties. I made a video on that too: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-UCtM-0Q28cs.htmlsi=WQvh1HIkdxkPZnIi
