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Match-moving with Lens Distortion
Merely knowing the amount of lens distortion and having a successful 3-D track is generally not sufficient, because most animation and compositing packages are not distortion-aware, or have different distortion calculation schemes. Similarly, if you have configured some correction for earlier image de-centering or cropping (ie padding) using the Image Preprocessor system, your post-tracking workflow must also reflect this.
When distortion and cropping are present, in order to maintain exactly matching 3-D tracks, you will need to have the following things be the same for SynthEyes and the compositing or animation package:
Undistorted shot footage, padded so the optic axis falls at the center,
An overall image aspect ratio reflecting the effects of padding and the pixel aspect ratio,
A field of view that matches this undistorted, padded footage, or,
A focal length and sensor (back plate) width that matches this footage,
3-D camera path and orientation trajectories, and
3-D tracker locations.
If a shot lines up in SynthEyes, but not in your compositing or animation software, checking these items is your first step.
Since SynthEyes preprocesses the images, or mathematically distorts the tracker locations, generally the down-stream software application will not receive matching imagery unless care is taken as described below to generate matching imagery. Some exporters will export commands to tell the downstream package how to reproduce the distortion, for example Fusion, Nuke, and After Effects (with the appropriate SynthEyes- supplied plugin installed, see the After Effects installation section).
SynthEyes has a script, started by the "Lens Workflow" button on the Summary or Lens panels, that simplifies workflow when dealing with distorted imagery. You need to run it before exporting in virtually all cases where lens distortion has been calculated. If you don't, you may have images with missing pieces, or excess trimming, or for the more advanced lens parameters, the images and animation simply won't match in the downstream application.
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