Radial Blur and focus effect - creates transparent/black edges

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Radial Blur and focus effect - creates transparent/black edges

I'm using Final Cut Pro 11. When I apply the radial blur effect or the focus effect, the edges of the video pull in and become transparent. It is forcing me to have to scale the footage in order for it to become usable. See the 2 photos below from my build and then 2 images from YouTube of another user.

I saw a tutorial on YouTube and the user's FCP was not demonstrating the same behavior.

Here is my radial blur

Here is the focus effect

And here is the YouTube video of a user using the same effects

Here's no edge transparency like on my version. Please help!

MacBook Pro 16″, macOS 14.7

Posted on Jan 2, 2025 8:15 AM

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Answer 1

Top-ranking reply

fox_m

Level 6

13,594 points

Jan 2, 2025 10:08 AM in response to damianwampler

The youtuber has the blur off-centered and there are "clear" regions going off the screen to the top and right. If you look closely in the bottom regions, you will see the edge darkening effect. This is due to the fact that the blur is fading the edges to "transparent".

If you want to get around this edge darkening effect with blurs, duplicate your clip with a copy that has no blurring on the bottom clip. However, you may find you prefer the original appearance as the edges will look "sharp".

If you have Motion, from FCP you can go to the Gaussian blur effect, right click and Open a copy in Motion. Find the Gaussian Blur applied to the Effect Source and from the Filters inspector, Publish the Crop option and Save. Then in FCP, apply the Gaussian Copy to the bottom clip and apply Crop. Adjust the blur Amount to match the edges of the top clip (but 50 should be about right).

Another option would be to use a Custom (solid) color background set to about 25% gray.

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