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[wired2film]

Hello everyone. I am trying to track a shot in Syntheyes and Import it into After Effects. The shot I am trying to track is of a Little Girl in front of a window. I am replacing her face with a skull for a couple of seconds and then it goes back to her face (this is for a horror film). The skull is a psd that was drawn by my animator and the tracker in AE doesn't work well enough for me to get a clean track. I've already exported a file from Syntheyes (.MA) and imported it into After Effects, but this is where I get confused. I don't know if I should be parenting the skull to the camera information or to one of the many null objects. When I parent it to one of the null objects nothing seems to happen, but when I parent it to the camera it just rotates ever so slightly. I don't do a lot of 3D stuff so consider me a newbie on this level. Also I was reading the help manual for Syntheyes and I didn't know if I should be doing an Object track and a Camera Track (the shot is hand held and there is some shake to it.) I've tried doing a object track, but I couldn't get it to solve. So to sum up what I am trying to achieve is track the girl's face so I can place a skull over her face in After Effects (6.5.1 Pro). Thanks in advance for any help.

[ssontech]

First, does the camera actually translate? If it is only a pan&tilt motion, then you need to do a "tripod" shot (nodal solution). If there is enough motion, you can do a camera track. Either way, you can parent the new image to one of the nulls in AE. You need to be sure you are "looking through" the camera imported from SynthEyes.

If the camera/face motion isn't really doing much, you might also do the tracking in SynthEyes, then export a 2-D track to AE. The fact that you're expecting to use a single image for the insert suggests this may be the case.

[wired2film]

Thanks for the response, but I'm not quite sure I know what you mean by the camera translate. The motion of the camera doesn't actually pan or tilt it's just a hand held shot that is trying to stay steady on the girl, but the camera moves around because it's a close up shot and they are not using any stablization on the camera. So I guess what I am asking is if it does move around, but maybe not that much your saying I should track it as if it were on a tripod (change the track type to tripod)? And the last question is how do you export a 2-D track, because that sounds like what I need to do since I am not really doing 3-D. I don't need to worry about the "Z" axis just the X and Y.

Thanks for the help.

-Brad

[ssontech]

It doesn't matter whether the camera is actually on a tripod, crane, dolly, hand-held, etc. What matters is what motion the camera makes:

translate==physically move a distance you could measure with a ruler
rotate==pan/tilt==look in different directions

Use the AfterEffects 2-D path exporter. See the manual's Exporting to Your Animation Package section, AfterEffects 2-D subsection.

[wired2film]

Thank you so much for the information. I'll give that a try.

-Brad