Camera¶
This panel contains all settings of the camera used for filming the movie which is currently being edited in the Clip editor.
- Camera Presets
Predefined settings can be used here. But such settings as distortion coefficients and principal point are not included in the presets and should be filled in even if camera presets are used.
- Sensor
- Width
Is the width of the CCD sensor in the camera. This value can be found in camera specifications.
- Pixel Aspect Ratio
Is the pixel aspect of the CCD sensor. This value can be found in camera specifications, but can also be guessed. For example, you know that the footage should be 1920×1080, but the images themselves are 1280×1080. In this case, the pixel aspect is: 1920 / 1280 = 1.5.
- Optical Center
Is the optical center of the lens used in the camera. In most cases it is equal to the image center, but it can be different in some special cases. Check camera/lens specifications in such cases. To set the optical center to the center of image, there is a Set Center button below the sliders.
Lens¶
- Focal Length
Is self-explanatory; it is the focal length with which the movie was shot. It can be set in millimeters or pixels.
- Distortion Model
Mathematical function to convert distorted to undistorted coordinates.
- Polynomial
Polynomial radial distortion.
- Division
It defines high distortions, which makes this model suitable much better for cameras with fisheye lenses.
- Nuke
Distortion model used by the Nuke compositor.
- Coefficients
Coefficients are used to compensate for lens distortion when the movie was shot. Currently these values can be tweaked by hand only (there are no calibration tools yet) using tools available in Distortion mode. Basically, just tweak K1 until solving is most accurate for the known focal length (but also take grid and annotations into account to prevent "impossible" distortion).
The coefficients of the division model work independent from each other and positive values will give a barrel distortion.
K1, K2 and K3