After using Pan or Zoom is any simple way to "reset" mask size to full screen? I understand I can come back and copy a Key Frame, but it seems you have to have one before you can copy it. Otherwise it is not the best experience trying to resize back to normal size manually. Thanks!
Could you not just split the file at the point you want it to return to normal before adding the effect to the first half of the clip? Or split the file after and use the 'Reset Video Effects' with a right hand click of the mouse?
Using the timeline, go to the point in the clip where you want the zoom in to finish and adjust to the size you want and then add the key frame Then forward to where you want to start zooming out and then add another keyframe. Then go to where you want the frame to start or end the zoom and set the size adjust back to 100%. I find it works better that way as sometimes the keyframe editor doesn't always want to add a keyframe where no adjustment had occurred. (meaning there had as yet been no adjustment to a frame for there to warrant adding a keyframe.) Once keyframes have been added you can slide them along the timeline if needed to a different point. The less keyframes that are added, the smoother the results.
If you want to apply the zoom to only a short section of the whole clip then yes, you need to cut at the beginning and end of the section to be zoomed and then apply the effect. Markers are only that, i.e specific points on the current timeline, they have no impact/effect on the actual footage played at that moment. If you "move" the video clip the marker will not "move with it".