Okay, I was watching this video tutorial: Video Copilot and the guy uses track motion at some moment. But I was wondering: How do you know what's a good track motion point? What are the important factors?

He's explaining it a bit here but not really quite, in my opinion.

Thanks in advance.

Right, this is an After Effects question I presume.

I suspect you're talking about the futuristic front door number tag tutorial on the videocopilot series.

In that case he wants to track an existing plate on the wall. To track that for perspective corner pin what better than the four corners. If I remember right he uses the screw headsused to mount the thing on the wall. but why? I think Andrew does mention it in passing but a good track point in that kind of example is a small shape that looks the same and to the same scale throughout the clip. i.e. the screw head is the same shap and size throughout the small clip he uses.

Also, the track point needs to stay in shot throughout the clip as well. Let's face it, you can't track it if it's off the screen can you?

So then, anything that stays the same through the clip but changes position is a good candidate. The track point works best if it has good contrast against the area around it so it stands out and can easily be 'found' frame by frame.

I hope this makes sense. Ask if you need more.

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Sorry, yes I meant After Effects.

Well, it was about how to create realistic artificial blood spatters on footage, and somewhere in the middle of this vid, Andrew uses track motion to keep the spatters in place.

Thanks a lot for the info, that cleared things up. I will experiment with the track motion a bit more and return if I come across any problems. Thanks again.

Not fanmiliar with that tut off hand. I suspect that he simply tracked a single point ona wall of something then to simply position the blood spatter with it.

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