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ddeveloping
12-06-2007, 05:47 PM
Hello, I'm new to AE. Anyways, I'm trying to track text to a building that has been filmed. The camera motion is not just a pan so the perspective changes quite a bit. I used corner pin and tracked a small part of the facade of the very easily. My question is how do I move the compositon out of the 4 pin track and retain perspective. I know this can't be done but in theory it seems like you could establish a vanishing point that could be tracked by setting up the 4 pin tracking. Like a plane that you could move stuff around in. Is it possible in any way to do this? Also, is there anyways to keep the 4 pin perspective track from resizing your content to fit the track (can you atleast keep it from changing the aspect ratio)? Thanks a million in advance!
Mylenium
12-06-2007, 07:37 PM
Hello, I'm new to AE. Anyways, I'm trying to track text to a building that has been filmed. The camera motion is not just a pan so the perspective changes quite a bit. I used corner pin and tracked a small part of the facade of the very easily. My question is how do I move the compositon out of the 4 pin track and retain perspective. I know this can't be done but in theory it seems like you could establish a vanishing point that could be tracked by setting up the 4 pin tracking. Like a plane that you could move stuff around in. Is it possible in any way to do this? Also, is there anyways to keep the 4 pin perspective track from resizing your content to fit the track (can you atleast keep it from changing the aspect ratio)? Thanks a million in advance!

No, not in AE. The tracker doesn't care for (co-)planarity. What you need is an app like mocha AE or a proper 3D matchmoving tool. Other thna that you could try exporting a reference frame to PS CS3 Extended and use vanishing point, then import the result back into AE. Might at least work for a part of the shot.

Mylenium
ddeveloping
12-07-2007, 12:57 AM
Ok i will look into that. Also, is there anyway for me to know how whatever is within the perspective 4 pin will be altered? it seems whatever i target for it it distorts it beyojnd recognition.
Mylenium
12-07-2007, 06:37 AM
Ok i will look into that. Also, is there anyway for me to know how whatever is within the perspective 4 pin will be altered? it seems whatever i target for it it distorts it beyojnd recognition.

Your problems are the same. Your distortion comes from the edges of the areas not being constrained and thus it distorts. I would also think that at some point you are simply getting to close to the track area in your footage and get heavy lens distortion which further complicates matters.

Mylenium
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12-07-2007, 06:37 AM
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