Lens Calibration Panel
The Lens Calibration panel provides the following information:
- Current lens calibration file
- A virtual “grid” that describes the number of zoom and focus data points that the calibration file is set for
- Points in the calibration file that have a valid calibration data point are filled in with a grey color
- The present position of the zoom and focus physical lenses as normalized to 0-1.
- The current “infinity distance” (the physical distance that correlates to infinity focus)
- The marker file with the coordinates of the markers for the calibration grid.
The lens system works by interpolating between valid lens calibration points. Lens calibration is covered in more detail in a separate chapter.
Since it’s difficult to calibrate a target at a focus distance of infinity, in practice the targets are calibrated at focus distances of about 1, 2, 3, 4, 5, and sometimes 7-8 meters away from the camera sensor location. For focus distances over this, the virtual focus distance is interpolated linearly from the last real focus distance (obtained from the nearest valid calibrated point) to the infinity focus distance value shown above.