Use Camera Model in the Undistort section to match the distortion shape in your footage. Start with the simplest model that describes the lens, then add complexity only when the shot provides enough reliable detail.
SIMPLE_RADIAL is the default for an unknown normal lens. Wide-angle footage is not automatically fisheye; reserve the fisheye models for genuine fisheye imagery.
Footage with no lens distortion
| Model | Use |
|---|---|
| SIMPLE_PINHOLE | CG, screen captures or already-corrected footage. Applies no lens-distortion correction. |
| PINHOLE | No distortion correction, with separate horizontal and vertical focal scaling. Consider it when the simpler model gives stretched proportions. |
Normal and wide-angle footage
| Model | Use |
|---|---|
| SIMPLE_RADIAL | Basic barrel or pincushion distortion with one adjustment. Start here for most unknown normal lenses. |
| RADIAL | Adds a second adjustment for stronger or more complex edge curvature. |
| OPENCV | Normal-lens curvature with uneven or off-center distortion correction. |
| FULL_OPENCV | More complex normal-lens correction. Use with a measured lens or strong static detail; weak coverage can produce unwanted warping. |
| FOV | A simpler wide-angle model controlled by overall strength. Consider it for edge stretching that is not full fisheye distortion. |
Fisheye footage
| Model | Use |
|---|---|
| SIMPLE_RADIAL_FISHEYE | The simplest starting point for genuine fisheye footage. |
| RADIAL_FISHEYE | Describes more complex fisheye edge curvature. |
| OPENCV_FISHEYE | A wide, strongly curved fisheye view. |
| THIN_PRISM_FISHEYE | Uneven or off-center wide/fisheye distortion, with strong analysis coverage. |
| RAD_TAN_THIN_PRISM_FISHEYE | The most detailed listed fisheye model. Use with a measured complex lens or enough reliable coverage to constrain the fit. |
Check the fit
Inspect the center and edges of the corrected plate. Check familiar object shapes, straight lines and image proportions. A complex model can still fit the wrong shape when useful scene information is missing.
If the result looks wrong, check whether the footage was already corrected, whether the lens is actually fisheye and whether the analysis range has reliable static detail. Compare a suitable simpler model before moving to a more complex one.
Return to lens calibration and STMaps to set the analysis range, samples and exports.
