Final Cut Pro out-transitions cut to black at the beginning instead of transitioning

OK. The problem is the underlying video is connected underneath the primary storyline. The project should not be laid out like that. Either the green background is on the primary storyline, or both the background and the alpha clip are connected above the primary storyline.

As I posted, the problem is in the layer arrangement. The background video should not be below the primary storyline. Video should be on the primary storyline or above it. Audio should be below the primary storyline. The problem you see is reproducible when the project layout is the way you show.

Well, I'll be ******... I had been experimenting this by using a generator on top of the blue background and it was working properly.

I just imported a clip with alpha channel and I'm seeing the very same thing as you.

For the Cross Dissolve, there is a viable workaround: use the Opacity handles.

Press Control-V to open the Video Animation pane; expand the one for Opacity and drag the handle in:

Here is another workaround that appears to be working: instead of dissolving out to nothing, I added a dummy clip and placed a Cross Dissolve between the two. This worked without affecting the background. Then I removed the dummy clip and it still worked.

I was experimenting with an HEVC file with alpha channel. It seems to be a hit or miss situation. I have seen it happen, and also at times it all works correctly. I tried moving stuff up or down.

Just now, I saw the problem, as you describe, with the background below the primary; moved both so the background was in the primary, and it worked correctly, again just as you described; moved them back to the starting position, and now it is working, and the background is below the primary. It is pretty inconsistent. I think I have been through all possible combinations of working correctly/not, and being above/below the primary...

This is an example of it working correctly, despite the video background being below the primary:

Also you can do it using the Video Animation pane. Control-V, click to open the opacity control and drag the handles to fade out (or in).

I’ve never seen that. What you’re fading out is a still image in the right sight of the screen? I’ve never seen the system dissolve do that. It doesn’t effect the layer below. The transitions you’re using look like they are altering the underlying image. Many Motion transitions do this.

Are you sure you used "Cross Dissolve" and not "Fade to Color" in this example?

Brie-Eating Surrender Monkey wrote:

It's a transition I created in Motion. I want this one because I wanted it to leave screen the way it came on at the beginning. But, okay, here's what happens when I replace the custom transition with the standard dissolve. No difference.

https://vimeo.com/695884474

Seriously, have you never seen this before? It's been a regular occurrence for me for 12 years, irrespective of what OS, version of FCP, workstation, at work or at home. Sometimes it does it, sometimes it doesn't, and I cannot find the pattern. Never have been able to. It's driven me to drink.

I'm not seeing that. I have an HD file with alpha PR4x4, and it fades out correctly with a cross dissolve when it's a connected clip and the background is on the storyline. It also works if both clips are above the storyline. It also works for a PSD with alpha or a PNG with alpha. What is your alpha image that behaves differently?

What transition are you using? If you just want the connected clip to fade out use a Cross Dissolve.

I use a cross dissolve in most every instance. Once or twice in many years I’ve come across having to right click on the dissolve and changing fade to black.