Desyncing content in timeline when adding transitions in video editing

You can always double-click an edit point to open up what I call the "transition editor" (I forget what Apple officially calls it). There you can quickly see and adjust for handles before/after adding transitions. Double-click on the edit point button and that will take you back out to the normal timeline editor.

In this example, the top clip has no handle to work with, the bottom clip has quite a bit of handle to work with. In this editor, I can actually grab each clip and slide them left/right to create exactly what I need before adding transitions.

TGGE wrote:

Thanks I was trying to learn how to make it work and make it easier for myself! Do you have any links etc for what apnea are did not understand that at all can guess but am not 100% sure.

apnea? Did you mean handles? See Ben's reply - handles are these extra media frames at either side of the transition.

TGGE wrote:

Thanks I was trying to learn how to make it work and make it easier for myself! Do you have any links etc for what apnea are did not understand that at all can guess but am not 100% sure. Also I thought compounds clips are just a bunch of clips that you combine together into one clip? Which means if halfway through I want to add a transition I won’t be able to?

I'd say "a bunch of clips that you combine together into one clip" is an appropriate description of a compound clip.

But you can always peer into the compound, and you can "undo" the compound ("break apart clip items") if need be.

To illustrate what I meant - say you have A1 and A2 on the primary storyline, with B1 and B2 above A1 and A2, respectively:

You could add two transitions at the playhead position above, which is what you have been doing.

If instead you combine A1 and B1 into a compound "C1", and similarly A2 and B2 into "C2",

then only one transition is necessary, and no problem with sync exists.

Are you talking about this:

A

B

The dissolves on the lower lane are shifted to the left? This can happen is there isn't enough extra media, handles on the clips, to overlap the clips properly without shortened the content. For one second dissolves you need a second on media handles on both the outgoing and the incoming clip to make the transition without changing the length.

In addition to Tom's solid advice:

If you are repeatedly doing the same thing - as I understand it, applying transitions at different "lanes" and trying to keep them in sync - you may want to make it easy on yourself.

There are ways that I can think of that may help.

1) Instead of applying transitions on different lanes, turn those into compound clips, and apply the transition just once. Note: before making the compound, extend both clips to create the necessary handles (extend them 1 second or so on each side, make the compound, and then trim the compound back 1 second; then you have a 1 second handle to use for the transition).

2) Create an effect that adds the clip above (or below). Then instead of having to deal with two clips and transitions on two lanes, there will be only simple transitions on the primary storyline.

Do this to see what’s happening. Put two clips that have not been trimmed into a new project. But a dissolve between them. You will get a warning. Make the dissolve and then double click the edit point to open the precision editor to see what’s happening.

If the clips don’t have enough handles, unused media beyond the edit point, on both sides of the edit point, the content might be shortened.

From How transitions are created in Final Cut Pro for Mac - Apple Support

Thank you Terry.

With clips here, I do mean video. Stills won't show the same behavior.

I call the "transition editor" (I forget what Apple officially calls it).

I think it's "precision editor".