create a video using clips with different framerates

Hey all,

I have a clip 4K 30FPS and another 4K 120 FPS. Which settings do I choose when creating a new project in FCP? What happens to the 120FPS if I want to create a project with 30FPS? Do I have the same quality if I create SlowMos of the 120FPS clip or are those already being compressed during the creation?

I hope you can help me with this.

Create a Project at the frame rate you're required to deliver in. If this is a personal project, then 30 is fine. All clips you drop into it will play as normal, FCPX conforms them automatically by adding fake frames or dropping existing frames as needed to match the frame rate of the timeline.

If you want slow motion, then 120 is the way to go. Select it, go to the retime menu (speedometer icon in tool bar just above timeline), and select Automatic Speed. This will conform the 120fps clip to play each and every original frame, so that you get in-camera, frame accurate slow motion, no faked frames. Retime as needed from there.

That really helped me! Thanks! I would've been stuck forever if I hadn't asked for help in this forum. Much appreciated!

Yeah that's the way I prefer to do it, as opposed to just relying on the first clip that hits the timeline. Although that can be great for doing quick mock ups.