Re: keyframe issue

Well, you'll have to play with the handles of each point, just like you would when making a path in Illustrator or Photoshop. Make the handles longer, and you'll slow down the speed around that point, make them shorter and you'll speed it up. The spacing of the small dots between the green points will show you the speed.

Unfortunately, I have not had much success smoothing motion paths in FCP - I get the same erratic behavior you are seeing now. I really prefer to leave FCP to simple editing and do any other motion in a program made for it, like Motion or After Effects. It is possible in FCP, though, just harder.

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Exploring the pitfalls of the 5D workflow. The many, many pitfalls...