Calibration results after optimization (with uncertainties):

Focal Length:          fc = [ 798.10138   818.90898 ]  [ 6.04336   5.73576 ]
Principal point:       cc = [ 341.86009   264.92583 ]  [ 3.69077   6.00517 ]
Skew:             alpha_c = [ 0.00000 ]  [ 0.00000  ]   => angle of pixel axes = 90.00000  0.00000 degrees
Distortion:            kc = [ 0.00000   0.00000   0.00000   0.00000  0.00000 ]  [ 0.00000   0.00000   0.00000   0.00000  0.00000 ]
Pixel error:          err = [ 0.25788   0.30175 ]

Note: The numerical errors are approximately three times the standard deviations (for reference).
