Final Cut Pro 10.4’s masks and mask effects are not 360° spherical video aware. When the edge of masks are blurred to make them softer – ‘feathered’ – the blur is not 360° aware. To make an edge blur consistent when looking around the sphere, the source equirectangular edge must be blurred much more nearer the top and bottom of the clip.
360° Mask Area 4D is in the Masks category of Alex4D 360° Effects:
Here is what the Final Cut Pro 360° viewer and the viewer look like when the 360° Mask Area 4D effect is applied:
The first set of parameters define control how opaque the inside area and outside area are:
Inside and Outside set the opacity of the parts of the clip inside and outside the area.
The Outside pop-up menu sets whether the area inside hides the outside area or not.
The next set of parameters define the area:
Area Centre, Area Size and Area Angle can also be set using the on-screen control.
Area Centre Limit stops the centre control from moving off the edge of the clip. Disable this if you want to keyframe this value so that the area can move off the edges of the clip.
Area Roundness controls the corners of the area. If Area Aspect Ratio is 1.0, a value of Area Roundness of 100 makes the area circular. A value of 0 makes the area sqaure.
Area Aspect Ratio defines the proportion of the width of the area to its height. 1 makes them equal. A value greater than 1 makes the area wider than it is tall. For example 2 makes the width twice the size of the height.
Area Feather controls the softness of the area edge.