A Final Cut Pro X plugin that applies a mask based on the transparency of a different compound clip and adds 360° feathering.

Part of Alex4D 360° Effects for Final Cut Pro 10.4: Essential VR video tools for 360° stories.

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° Add Mask and Feather 4D uses the transparency of a separate compound clip to define a mask, so that the edge can be feathered to help compositing clips over other clips.

360° Add Mask and Feather 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° Add Mask and Feather 4D effect is applied:

Tutorial – Feathering a mask applied to a 360° clip

Go to the Masks section of the Final Cut Pro effects browser, Apply Draw Mask to your clip.

Click and drag in the viewer to edit the mask you want to add to your clip.

Make a duplicate of the clip in the timeline by dragging upwards with the Option and Shift keys held down.

Control-click the duplicate and use the context menu to turn it into a compound clip.

Disable the clip by pressing the V key. Shift-drag it below the original clip.

Delete the Draw Mask effect from the original clip.

Apply the 360° Add Mask and Feather 4D effect to the original clip.

Click the Drop Zone parameter.

Click the disabled masked compound clip to select it as the source to the Drop Zone. 

The mask from the compound clip is applied to the original clip with a feather.

If you then change the Draw Mask mask applied to the clip in the compound clip…

…the feathered mask applied to the original clip is updated.


Mask Source selects the clip whose mask is to be used.

Show Mask shows the mask only.

Inside and Outside control the opacity of the inside and outside areas of the clip.

The Outside pop-up menu sets whether the area inside hides the outside area or not.