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T-bat
04-23-2005, 04:31 PM
Hi,
probably stupid question, but when you're compositing elements into shot, do you have to frame them where you want them to be in shot or frame them centered? When you're compositing do you have to undistort them, composite elements and provide some distortion? Or composite them undistorted? Shot everything with longer lens?

beaker
04-23-2005, 08:35 PM
probably stupid question, but when you're compositing elements into shot, do you have to frame them where you want them to be in shot or frame them centered?You can frame them however you want. Framing makes no difference.

When you're compositing do you have to undistort them, composite elements and provide some distortion? Or composite them undistorted? Shot everything with longer lens?
You have to composite 3d elements on undistorted plates. Pending you have distortion, you first need to undistort them and use that for your tracking/matchmoving. Though most camera matchmovers have distortion compensation build in. In your comp redistort both 2d and 3d elements together at the end of the pipeline.

Cman
04-24-2005, 12:01 AM
You can frame them however you want. Framing makes no difference.
...

I would agree with this mostly - however I have experienced that a vertical shift of the subject can cause unacceptable softness - so I tend to try to make the subject vertically appropriate to the final composite when dealing with interlaced footage.

T-bat
04-25-2005, 02:22 PM
So when distortion is not noticeable you composite normaly. What would you do when you was given a shot which was filmed with shorter lenses. You have to add those nice smoke elements filmed with normal lenses and explosion filmed with long lenses. Are you just going to layer them? When I should care about distortion?

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04-25-2005, 02:22 PM
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